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Flashcards in SC Revisit List Deck (119)
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1
Q

Confidence in X vs Confidence that X

A

Confidence THAT . Ex: According to some analystis, the gains in the stock market reflect the growing confidence that the economy will avoid a recession. Confidence IN .Ex: She has confidence in your ability.

2
Q

What is “fashioned”? The empire? or the deities? Many of the earliest known images of the Hindu deities in India date from the time of the Kushan Empire, fashioned from spotted sandstone.

A

This sentence is saying the empire was fashioned. the “, -ed” structure modifies the main noun before the comma. In this case, that noun is “empire”. That is illogical.

3
Q

What two things are wrong with this sentence?: His studies of ice-polished rocks in his Alpine homeland, far outside the range ofpresent-day glaciers, led Louis Agassiz in 1837 to propose the concept of an age when great ice sheets had existed in current temperate areas.

A

1: “current temperate” should be “currently temperate”; this is because “currently” modifies the adjetive “temperate”, therefore “currently”needs to be in adverb form. 2: “had existed” is past perfect, which is used to denote the longer-ago of rtwo past actions. There aren’t two past actions in this sentence… don’t use a more complex trense whena simple tense is acceptable. Should be “existed”

4
Q

As a means ____ ?

A

“As a means OF” and “As a means to” are correct. “As a means FOR” is incorrect

5
Q

Attribute X as Y?

A

No! Attribute X to Y.

6
Q

A report by the american academy for the advancement of science has concluded that (MUCH / MANY) of the currently uncontrolled dioxins to which North Americans are exposed to come from the incineration of wastes.

A

MANY. MANY = Countable; MUCH = Uncountable; Memorize: Many bottles of water. Much water.

7
Q

what parallelism marker for the following sentence: Ulcers are caused not by stress but by a bacterium in the stomach.

A

Not X but Y

8
Q

How does “, with” structure work?

A

”, with” refers to the subject +verb + object of a preceeding clause. For example: “The dog barked happily at the moon, with joy exuding from every fiber of his being.” The joy isn’t exuding from the moon, the joy is exuding from the happily barking dog. Watch out for a trap where GMAT tries to use “, with” in the same context as “, which”…

9
Q

In an effort to reduce their inventories, Italian vinters have cut prices; their wines are priced to sell, and they (do / have).

A

do The do sell. Not: they have sell…. makes no sense

10
Q

What’s wrong with this sentence?: Expectations are for heating-oil prices to be higher this year than last year’s because refiners are paying about $5 a barrel for crude oil more than they did last year.

A

“$5 a barrel for crude oil MORE” is incorrect. The barrel is MORE expensive, not the crude oil itself. Thus, “more” is incorrectly placed. should be “$5 a barrel MORE…”

11
Q

What is a comma splice?

A

A comma splice incorrectly connects two independent clauses. If the clauses are independent, SPLIT THEM UP into two seperate sentences or put a conjunction after the comma. It is that simple: Comma Splice: My family bakes together nearly every night, we then get to enjoy everything we make together. Correction 1: My family bakes together nearly every night. We then get to enjoy everything we make together. The comma splice has been corrected by breaking the sentence into two separate sentences. Correction 2: My family bakes together nearly every night, and we then get to enjoy everything we make together. The comma splice has been corrected by adding a coordinating conjunction and a comma. Correction 3: After my family bakes together nearly every night, we get to enjoy everything we make together.

12
Q

What does the “em dash” mean?

A

“em dash” indicates a rephrasing of something written earlier in the sentence; the em dash means “in other words”. this means it must comply with parallelism construct. that X – that Y …

13
Q

What is wrong with this sentence?: (if anything): Heavy commitment by an executive to a course of action, especially if it has worked well in the past, makes it likely to miss signs of incipient trouble or misinterpret them when they do appear.

A

The first “it” refers to the *course of action*. The second it, though, is a dummy pronoun; it doesn’t refer to any particular noun in the sentence. While a dummy pronoun is acceptable in general, the two instances of it don’t refer to the same thing. This is considered ambiguious.

14
Q

What does “whose” refer to in the following sentence: “As a result, presidential elections have become referendum on the business cycle, whose fortuitous turnings are erroneously attributed to the President.” ?

A

Business cycle “whose” refers to the previous referable noun. “Whose” is a possessive pronoun that can only refer to a person (or people). Here are some examples of proper use: The person whose car I’m driving is away on vacation. I’m house sitting for my cousin Vinny, whose television is broken. Last month I saw a movie about 8 coal miners from Virginia, whose lives are very interesting.

15
Q

What (if anything) is wrong wit this sentence: As rainfall began to decrease in the Southwest about the middle of the twelfth century, most of the Monument Valley Anasazi abandoned their homes to join other clans with less limitations on water access.

A

LESS should be FEWER because “limitations” are countable: (one limitation, two limitations,etc.”)

16
Q

What (if anything) is wrong wit this sentence: Marconi conceived of the radio to be a substitute for the telephone, a tool for private conversation, other than what it is, precisely the opposite, a tool for communicating with a large, public audience.

A

Conceive of the radio TO BE a substitute is incorrect. Should be Conceive of the radio AS a substitute. Conceive X as Y is the correct idiom.

17
Q

What is wrong with this sentence?: (if anything): A mutual fund having billions of dollars in assets will typically invest that money in hundreds of companies and rarely do they hold more than one percent.

A

Meaning: is there a causal relationship between investing and owning less than 1% of shares? If so, shouldn’t have “and”. Should be something like: “A mutual fund having billions of dollars in assets will typically invest that money in hundreds of companies, rarely holding more than one percent of the shares of any particular corporation.” Another example: “Xiao visited the shoe store and she bought some milk.” Is there a cause and effect relationship betwen visiting the shoe store and buying milk? NO! therefore, keep “and” as they are INDEPENDENT.

18
Q

What is wrong with this sentence, if anything?: Starfish, with anywhere from five to eight arms, have a strong regenerative ability, and if they lose one arm it is quickly replaced, sometimes with the animal overcompensating, growing an extra one or two.

A

if X (then) Y requires parallelism. This sentence says: if they lose one arm … (then) it is quickly replaced. If X (then) Y requires that the subject pronoun in the second clause should refer to the subject of the first clause. Can’t have If THEY… (then) IT …

19
Q

As X as Y

A
20
Q

REMEMBER: -ing word that is behind a noun is a modifier:

A
21
Q

Diabetes ranks as the nation’s third leading cause of death, surpassed only by heart disease and cancer.

A

In this sentence, it will not make sense for verb-ed modifier to modify the preceding noun “death”. Death cannot be surpassed by anything. Hence, the verb-ed modifier is modifying noun phrase “the nation’s third leading cause of death”. Now the reference makes sense and the modifier establishes the fact this particular cause of death is “surpassed only by heart disease and cancer”.

Structurally, the verb-ed modifier is modifying the preceding noun phrase “the nation’s third leading cause of death”.

22
Q

Singing a beautiful song, Mary mesmerized everyone present in the room.

A

So how did Mary mesmerize everyone? By singing a beautiful song. Here the verb-ing modifier is modifying the entire clause.

When placed in the beginning of the sentence followed by a comma, it always modifies the subject of the clause.

23
Q

Steps to solve absolute value problems?

A

Method 1: Number Line for inputs:
Draw 2 number lines:

1 for negative inputs of x and y

2 for positive inputs of x and y

calculate YES/NO answer to inequality question for each number line input.

Method 2:

Step 1: Draw each function graph for (1) and (2)

Step 2: Apply absolute value to each function graph in (1) and (2)

Step 3: answer Yes/No for inequality question.

24
Q

Translate this to an equation:

Martha paid 10% more for the Armchair than the Coffee Table.

A

(1.1) * C = A

25
Q

What, if anything, is wrong with this sentence?
The original building and loan associations were organized as limited life funds, whose members made monthly payments on their share subscriptions and then took turns drawing on the funds for home mortgages.

A

Nothing!
X and then Y requires parallelism.

“… MADE payments and then TOOK turns…”

26
Q
A

C

Note: B may be tempting, however, you must insert either a ; or a conjunction in between two independent clauses.

Also, the idiom is “except in”

27
Q
A

C

28
Q

What, if anything, is wrong with the following sentence:

Australian embryologists have found evidence suggesting that the elephant had descended from an aquatic animal with its trunk originally evolved as a kind of snorkel.

A

The preposition “with” is incorrect here, because it is connecting two complete sentences. Two complete sentences must be connected with “and”. This is the equivalent of writing:

“The elephant is gray with its trunk is long”… as opposed to “The elephant is gray, and its trunk is long.”

Likewise, “had descended” is incorrect. The correct usage of “had descended” requires a separate event or time marker at a more recent time in the past.

29
Q
A

C.

30
Q
A

E!

The idiom “dated at” is a correct idiom.

From answer (c) the idiom “dated to be” is incorrect.

31
Q
A

C!
Note: X than Y. Must be COMPARING apples to apples.

Whenever there is a comparison marker, make sure it compares APPLES to APPLES.

32
Q
A

When you see AND, make a check for parallelism!!!

33
Q
A

Remember: Read the preceeding words when evaluating a split! No other way to catch the incorrect sounding idom “depends on if” vs. “depends on whether”

When to use “if”

The word “if” is used for clauses that specify conditions or speculate on something hypothetical.

  1. ) Condition: “If you finish your peas, you can have dessert.”
  2. ) Hypothetical: “If I regularly ate my vegetables, I probably would be healthier.”

GMAT Sentence Correction: If vs. Whether

BY MIKE MᶜGARRY ON MAY 29, 2012 IN GRAMMAR, PHRASES AND CLAUSES, SENTENCE CORRECTION, VERBAL

“I don’t know if you will find this post helpful”

Do you spot the error in the preceding sentence? This error is common in casual spoken English, but it will cost you on the GMAT Sentence Correction. In that sentence, the word “if” is incorrect: it should be replaced by the word “whether.”

When to use “if”

The word “if” is used for clauses that specify conditions or speculate on something hypothetical.

  1. ) Condition: “If you finish your peas, you can have dessert.”
  2. ) Hypothetical: “If I regularly ate my vegetables, I probably would be healthier.”

In formal logic, the clause following the “if” clause would begin with the word “then”: that’s perfectly acceptable grammatically, but not at all necessary. For example, in both of those sentence, the word “then” could be inserted right after the comma, and would add a bit of emphasis to the logical relationship, if that were something that needed underscoring.

The last clause of the previous paragraph highlights a particular category of conditional statements: those that use the subjunctive. For more on the subjunctive mood, see this post. The GMAT loves “if-” clauses involving the subjunctive.

When to use “whether”

The word “whether” is a relative pronoun, which means it introduces a relative clause. A “whether” clause is always about the uncertainty in a choice or alternative, and the clause itself may stand apart from the sentence — the way an “if” clause does — or may act as a noun. When it stands apart, it is like an “if” clause in which the definite causal nature has been replaced with uncertainty or irrelevance. When it acts as a noun, the clause may act as the subject of the sentence, or as the object of an epistemological verb (to know, to wonder, etc.) or a volitional verb (to care, to prefer, etc.)

Stands apart:

  1. ) Whether you study French or Spanish, you will encounter an unfamiliar language in Japan.
  2. ) Whether or not I get the raise, I am going to buy that new car.

Notice that if we removed the uncertainty of the choice in either of these, we could replace the word whether with the word “if” to get a more definitive conditional statement. Without making those changes, the word “if” would be wrong.

Subject of sentence:

  1. ) Whether you like jazz will influence your opinion of this new club.
  2. ) Whether I walk on her left or right side matters a great deal to her.

Object of an epistemological or volitional verb:

  1. ) I don’t know whether there is intelligent life elsewhere in the Universe.
  2. ) He doesn’t care whether you serve broccoli or Brussels sprouts with dinner.

In sentence #5-8, the word “if” would be 100% incorrect. The GMAT Sentence Correction loves to test that particular mistake.

34
Q

, verb-ed structure

A

Similar to “, which”. Modifies the modifies the preceding NOUN

35
Q

Whether vs If

A

Use “whether” for uncertainty. (when meaning is “whether or not”).

Better to think of “If” as a condition – If X Then Y”.

36
Q
A

you CAN have different tenses, in parallel OR not in parallel, when appropriate for the context/meaning. “I ran yesterday and will run tomorrow.” Your trigger to check parallelism is the markers In this case “that many had feared earlier in the year” is modifying “recession”. We have many different tenses here – this is past perfect because of the time marker “earlier in the year”. Then we have present tense “reflect”. Finally, parallel structure using future tenses– “will avoid…and (will) come” The “will” applies to both “avoid” and “come”, but “will” is not repeated the 2nd time. As discussed, these “helper” words can be repeated OR not repeated for parallelism. “I will run tonight and throw tomorrow”. OR “I will run tonight and will throw tomorrow”

37
Q

Which tense indicates ONGOING action?

had become

vs.

has become

A

has become indicates ONGOING action.

“had become” is PAST perfect – it does NOT require ONGOING – it is used to show the time frame before other past tense verbs, or a specific time marker. PRESENT perfect (HAVE become) is used for ongoing.

See image for example usage of past perfect:

38
Q
A

1) Think of “whereas” sort of like a comparison marker, but not AS strong, not as strong as “Unlike X, Y”, for example. Likewise, you can indeed start a sentence with “whereas”.
2) The idiom is “Whereas X, Y”.
3) Semi-Colon means clauses must be independent. Place eye focus and emphasis on the end of the sentence. Can often ignore beginning.
4) While: “While” can actually mean two things:

1) while = at the same time as. I practice piano while twiddling my thumbs. (I’m very talented!) I practice piano at the same time as I twiddle my thumbs.
2) while = although, or some sort of contrast. While it’s true that I play piano and know how to twiddle my thumbs, I obviously can’t do both of those things at the same time. That would be impossible!”

39
Q
A
  1. Vertically scan for splits.
  2. “and” is a trigger word. Search for “and” on SC’s. Always.
  3. When using “and” make sure that each side of the “and” makes sense by itself. Ex: “The earth’s core rotates independently of and more quickly than…” is much better than the incorrect: “The earth’s core rotates independently and more quickly than…”.
40
Q
A

Until recently, the Inuit people led a nomadic existence, sheltering in igloos, the ice-block domes that are peculiar to north-central Canada, and in structures made of stones, bones, driftwood, and skins.

A. Until recently, the Inuit people led a nomadic existence, sheltering
ANSWER: The list starts after “sheltering”. “In igloos” is parallel to “in structures”.

B. During recent times, the Inuit people lead a nomadic existence, sheltering
PROBLEM: You can’t say “during recent times.” During has to be an isolated time frame (During the next five years, during the war, etc.). Also, it would set up present perfect tense, not the present tense.

C. In the times that are recent, the Inuit people led a nomadic existence, sheltered
PROBLEM: “In the times that are recent” is ridiculous, and the past tense wouldn’t make sense (but little here does).

D. Up until recently, the Inuit people, leading a nomadic existence, have sheltered
PROBLEM: The “up” is unnecessary. The present perfect tense starts in the past and continues into the present. But the use of “until recently” implies that this has stopped, so the present perfect doesn’t work.

E. Until recent time, leading a nomadic existence, the Inuit people were sheltered
PROBLEM: “Until recent time” is gibberish. “leading a nomadic existence” isn’t modifying the Inuits anymore.

When I see “, and” make special note that each side of the and must either be (A) parallel, or (B) two independent clauses. In this case parallel is the answer.

1) the “, sheltering” in (1) refers back to the entire subject + verb of the preceding clause.
2) Check immediately after the “and” for a preposition. If there is a preposition “, and in…” this means that parallelism must exist.

41
Q
A

As X as Y

More X than Y.

Sniper for the correct idiom.

42
Q

On the GMAT Which idiom is preferred?

a) As opposed to
b) instead of

A

Instead of

43
Q
A
44
Q
A

Remember the “If X then Y” trigger!

45
Q
A
46
Q

Whether vs. If

A

Whether = CHOICE between two of the same object.

If = Conditional AND Hypothetical

If Condtional: If X then Y.

If Hypothetical: If I work hard, I will succeed.

=============

“If” is generally used for reasoning .. If/ then type of sentences… If this happens then this will happen.
Eg- If you finish your work by Five, you can leave early

and for Hypothetical sentences
Eg- If i work hard, I may get a good score in GMAT

“Whether” is used when we have choice between two options.
Eg-I need to decide whether i should Call her for the movie
I dont know whether i should study or go on my friends birthday

47
Q
  1. A team can be “comprised of”/ “comprise” certain members.

OR

  1. Certain members can “comprise”/ “be comprised of” the team.
A
  1. A team can be “comprised of” certain members.

OR

  1. Certain members can “comprise” the team.
48
Q
A

Note that E has redundancy. Good thing to watch out for!

49
Q
A
50
Q
A

I choose B.

Subject verb agreement. Subject : ‘Sculpted boulders’ - plural.
So we need plural verb - ‘include’
So A and D are out.

In C, ‘earliest of monumental art’ is different from ‘the earliest monumental art’. Meaning.
In E, meaning has changed. E tells that the Boulders and human figures are two different t

51
Q
A
52
Q

Correct? Y/N

A
53
Q
A
54
Q
A
55
Q

Note: look at the structure: X but Y.

I got this wrong first time because I didn’t pay attention to the tiny deflecting words that were incorrectly placed.

A
56
Q

I origially chose (a). When you are faced with a question like this, pay attention to meaning differences as sentence fragments are re-arranged around. Think about meaning changes!!!

A
57
Q

Carbon-14 dating reveals that the megalithic monuments in Brittany are nearly 2,000 years as old as any of their supposed Mediterranean predecessors.

(A) as old as any of their supposed
(B) older than any of their supposed
(C) as old as their supposed
(D) older than any of their supposedly
(E) as old as their supposedly

A

In A, C and E, nearly 2000 years as old as makes no sense. The intended meaning of the sentence is that the monuments are nearly 2000 years older. Eliminate A, C and E.

In D, supposedly Mediterranean changes the intended meaning of the sentence. The sentence is not about origin – whether the monuments actually were Mediterranean – but about age: whether their supposed…predecessors actually were predecessors. Eliminate D.

The correct answer is B.

58
Q

When can you use “do to” ?

A

Rule: can only be used when you can swap “do to” with “caused by” and it still makes sense.

“Do to” must modify nouns only.

Ex:

The parent-teacher meeting was canceled due to heavy rains. – INCORRECT

‘Due to’ modifies the action in the preceding clause and hence is not used correctly.

The parent-teacher meeting was canceled caused by heavy rains. – INCORRECT

Note how when “due to” is replaced with “caused by”, the sentence no longer makes sense.

The parent-teacher meeting was canceled because of heavy rains. – CORRECT

59
Q

Subjunctive Examples: Just like Portugues— look for the trigger!

A

If I were president, things would be different. (Regular indicative form would be “I was”)

I wish Jim were able to play the trumpet. (Regular indicative form would be “Jim was”)

His mother insisted that he shave his beard. (Regular indicative form would be “he shaves”)

The instructions recommend that she clean her shirt right away. (Regular indicative form would be “she cleans”)

60
Q
A

C has the correct construction of “not by X, but by Y”

this question tests your knowledge of parallelism

The correct idiom is “not X but Y”. X and Y must be parallel

Note that A and B have a construction “not CAUSED …….. but Y’
If the writer wants to write that way, it should be “not CAUSED X, but CAUSED Y”

In this case, X and Y both have to have a “by” inside them.
The only alternative that has a structure “caused not by X, but by Y” is C

61
Q

correct? Y/N

A

Y!

62
Q

”, who” refers to noun preceding! Just like “, -ed”, “, which”, etc.

A
63
Q

”, with”

A
64
Q

What is triggered when I see a semi-colon?

A

BOTH SIDES of the semi-colon must be INDEPENDENT clauses. If they are, then semi-colon placement is OK.

65
Q
A

Avoid redundancy!

66
Q

Tell me why D is wrong.

A

D is wrong because “Modifier touch” rule. “that” acts as a modifier on kings, and clearly D makes no sense when you realize this.

67
Q
A

When you see a time marker ==> had + -ed is more acceptable!

ex: “By 1945, the United States had been at war for several years.

Also: REMEMBER THAT TENSES DONT ALWAYS HAVE TO MATCH 100%! Must match the CONTEXT!

68
Q

Why are A+B higher probability to be wrong as compared to C, D, & E?

A

The common split you want to notice here (at start of underline) is “that + active Verb” is much more commonly correct than “preposition + modifier”.

Also–as a side note–notice that the verb “has” is just acting as a normal verb that means “possess”. As opposed to Present Perfect tense, where “has” is a helping word– “He has worked”.

I have a tendency to discount “has” out of the gate… note that it must be coupled as a helping verb: “we have been freiends for years”… “He has been gay for years”.

69
Q

Q: What do I do when I don’t find grammatical errors in two SEPARATE answer options?

A

A: CHECK FOR MEANING ERROR!!!

The first thing to check is what you mentioned. The best way to find the meaning errors is to eliminate the clear grammar errors first, and then compare the meanings. You should not see a grammar error in B or E– then, compare B and E for meaning

70
Q

What is the idiom that makes A correct?

A

The idiom “So _ that __” is ok. The Blanks don’t need the exact same structure here

71
Q
A
72
Q

What does “, which” refer to?

A

ALWAYS THE NOUN JUST BEFORE THE COMMA! the “and” threw me off last time. the “, which” still refers to “prices”

73
Q
A

Note: you can use “when” correctly and have it not refer to a time/place. Ex: “I eat when I’m hungry”.

74
Q
A
75
Q

Does Dispite X, Y require apples to apples comparison?

A

Yes and no, it is not exactly the same as “Unlike X, Y”. It requires parallelism, but not necessarily apples to apples comparison.

76
Q

Semicolon practice:

A

When faced with a semicolon (or more than one) in the answer choices, your instinctive reaction should be to judge quickly whether the clauses on both sides are independent; if both clauses are not, that answer with the semicolon is incorrect.

BOOM!

77
Q

Correct? Y/N

“Emily and Nora fell asleep, with Emily still having wet hair.”

A

No!

with “, with” that is after a noun—This doesn’t work, because Emily is not a sub-component of Emily.
Generally, the noun should be some component of the previous subject.

ex:
James was injured badly in the accident, with three bones broken badly enough to require surgery.

or

Matt has a very full schedule this week, with every one of his available time slots occupied.

78
Q
A
79
Q
A

“Whose” here is a pronoun ambiguity issue – it might seem to refer to “predator”, but we are still talking about the Narwhals. Parallel verbs – “they seek… and their migrations follow” It’s common to repeat the same pronoun / structure, but it depends on meaning. Here we have “they seek” and “their migrations follow” – not exactly the same, but both “they” and “their” clearly refer to the narwhals. We can have a change in subject –> He runs and she jumps.

80
Q
A
81
Q

How does “, with” compare to “, -ing” ?

A

The diet of the ordinary Greek in classical times was largely vegetarian-vegetables,
fresh cheese, oatmeal, and meal cakes, with meat as a rarity.

Here “with” adds modification to the verb phrase “diet was largely vegetarian”. You could probably replace it with an -ing modifier like “including meat only on rare occasions”.

look for instances wherein “, with” could be repalced with “, - ing”. They are almost equivalent.

“,with” behaves similarly to “,verb-ing”.

82
Q

The parent-teacher meeting was canceled (because of / due to) heavy rains

A

Because of!

‘Due to’ is correct if the sentence makes sense when you replace ‘due to’ with ’caused by’. If, it does not, then use of ‘due to’ is not correct

The parent-teacher meeting was canceled due to heavy rains. – INCORRECT

‘Due to’ modifies the action in the preceding clause and hence is not used correctly.

The parent-teacher meeting was canceled caused by heavy rains. – INCORRECT

Note how when “due to” is replaced with “caused by”, the sentence no longer makes sense.

The parent-teacher meeting was canceled because of heavy rains. – CORRECT

‘because of’ modifies the action in preceding clause, indicating why the meeting was canceled.

The cancellation of parent-teacher meeting was due to heavy rains. – CORRECT

Note: due to must modify a noun. ex: “Her high score was due to diligent study.” “due to diligent study” modifies “high score”.

83
Q

If x is the number of positive integers that will leave no remainder when divided into 1,880, what is the value of x?

Note: 1880 = 2^3*5^1*47^1

A

16

84
Q

How many trailing zeros (zeros to the right of the last non-zero digit of a number) are in 25!?

A

6.

Note: Question is basically asking how many 2*5 pairs exist in 25!

Common trap I’ve fallen for is to FORGET ABOUT SQUARES!

Ex: 25 = 5^2.

This means there are 6 5’s being multiplied and 12 total 2’s, which would make 6 5*2 pairs! boom!

85
Q

All factorials except 1! and 0! are ____.

A

EVEN!

All it takes is a single 2 in the multiplication to become even!

86
Q

Z=7*3*k and Z=13*3*j

What is the minimum value of Z ?

13*3*7 = 13*3*7

A
87
Q

What is the first step to attacking this problem?

A

xyz must be a perfect square. In a perfect square, all of the powers of prime factors are EVEN! AKA, there cannot be an odd number of any prime factor!

Answer is C

C) 2^8 * 3^2

BOOM

💥💥💥💥💥💥💥💥💥💥💥💥💥

88
Q

X is a multiple of A and B, what can we conclude?

A

X is a multiple of the LCM of A and B

Ex:

X is a multiple of 8 and 12, therefore X is a multiple of 24. Also, min value of X is 24

89
Q

How many 2’s are in 11 ! ?

A

8 2’s!

Remember:

8=2^3

4=2^2

so there are 5 2’s with those two numbers alone. Then you get the other 2 from:

2, 6, 10

double count and watch out for square and cube powers and how often I need to account for them!

90
Q

The number 36.12 is the result of a division, what is the remainder of that division?

A

We don’t know.

We know the remainder is the *unsimplified* numerator of 12/100, however it isn’t clear if the remainder is 12, 24, 36, 3, etc. because 3/25 = 12/100 = 24/200 = 36/300

91
Q

does 3 divide into 3?

does 3 divide into 12?

does 12 divide into 3?

A

does 3 divide into 3?

YES

does 3 divide into 12?

YES

does 12 divide into 3?

NO

Note: does X divide into Y just means: is Y/X an integer? Is Y a multiple of X?

92
Q

Q: How many leading zeros to the right of the decimal point will 1/7! – aka: (1/5040) have?

A

A: 3 leading zeros to the right of the decimal point.

If X is an integer with k digits, then 1/x

will have k – 1 leading zeros unless X is a perfect power of 10, in which case there will be k – 2 leading zeros.

93
Q

X divided by 21 gives a remainder of 5.

What is the remainder of X divided by 3?

What is the remainder of X divided by 7?

A

What is the remainder of X divided by 3?

A: 2

What is the remainder of X divided by 7?

A: 5

If a number leaves a remainder ‘r’ (the number is the divisor), all its factors will have the same remainder ‘r’ provided the value of ‘r’ is less than the value of the factor.
Eg. If remainder of a number when divided by 21 is 5, then the remainder of that same number when divided by 7 (which is a factor of 21) will also be 5.

If the value of ‘r’ is greater than the value of the factor, then we have to take the remainder of ‘r’ divided by the factor to get the remainder.
Eg. If remainder of a number when divided by 21 is 5, then the remainder of that same number when divided by 3 (which is a factor of 21) will be remainder of 5/3, which is 2.

94
Q

What are the cycle of powers for 2 and 3?

A
95
Q

What is the remainder of 20*27/25?

A
96
Q
A
97
Q

What are two ways to express 7/4?

A

Remember:

Dividend/Divisor = Quotient + Remainder/Divisor

7/4 = 1 + ¾.​

If we multiply through by the Divisor, we get:

Dividend = Quotient*Divisor + Remainder.

7 = 4*1 + 3.​

98
Q
A

Solution: A

The correct response is (A). There’s a nice parallelism in the original sentence with “known THAT…and THAT.”

If you chose (B), here we’re missing the parallelism for the second clause. There are two things that were “known.”

If you chose (C), the addition of the word “also” is wordy and not needed. Additionally, changing “as” to “like” changes the meaning of the sentence. The sentence is not drawing a comparison.

If you chose (D), the pronoun “them” is plural and cannot be used to refer to the singular antecedent “electro-magnet.”

If you chose (E), “and also known” is not parallel with the relative clause at the beginning of the sentence. The GMAT often uses the parallel construction: VERB + “THAT”….and THAT…

99
Q
A
100
Q
A

Correct answer? D.

Why is A incorrect? Past perfect refers to the longer ago of two actions!

See image:

101
Q
A
102
Q
A
103
Q
A

C.

Reduced X, Y, and Z.

B is wrong because “reduced raised” doesn’t make any sense. Always try to apply intro verb to every parallelizaiton element. This will help me find parallelization.

104
Q
A

D

105
Q
A

E is correct. Note: I am tempted to think the modifier at the end of the sentence is unnecessary, however, it is an appositive modifier.

Proper appositive construction means you place a comma between modifiers that are not required:

For example, note the following sentence:

Like the Great Horned Owl, the Bald Eagle, America’s national bird, has few natural predators, yet its population dwindled to almost nothing until DDT was banned.

The sentence properly uses the appositive construction in using the name “Bald Eagle” — and then a comma for the non-vital appositive description “America’s national bird.”

106
Q
A
107
Q
A
108
Q
A
109
Q
A
110
Q
A
111
Q
A
112
Q
A
113
Q
A

A.

For B: “in Edith Sampson” ==> Wrong. Also, Modifier “in 1950” should be as close to what it is modifying.

114
Q
A

A.

Note that A has the following structure:

As a result of ____ and because ____

Important: parallelism can match the FEELING, doesn’t HAVE to be because X and because Y..

Ex:

In X and on Y:

I worked in the kitchen and the den.

I worked in the kitchen and on the roof.

Why is C wrong?

Likewise, “Being” is almost always incorrect.

115
Q

Idiom?

A

The more so… ?

116
Q
A

D.

“X and Y” doesn’t necessarily always mean two separate events.

117
Q
A

C

118
Q
A

C

“That” refers back to community!!!

“That” normally refers to whatever is RIGHT before it.

(Similar to “which”)

One of the dogs is blue.

One of the dogs that are blue ran fast.

119
Q

John cooks better pizza than his wife.

Ok?

A

Yes. This is okay because john is not a cannibal!

There are two possible comparisons, yet only one of them is logical:
John cooks pizza better than his wife [cooks pizza].

John cooks pizza better than he cooks his wife. (🚨🚨illogical comparison!🚨🚨)

  1. Choose the answer choice that conveys intended unambiguous comparison.
  2. When the sentence conveys ambiguous comparison, repeat either the preposition or the helping verb to convey the intended meaning.