if positive integer n is divisible by and 7, then n must also be divisibile by which of the following.?
I. 12
II. 35
III. 70
Answer I is out of the question since n is a multiple of 35. However, why is choice III 70 wrong.
QA is C
og math # 37
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Some of the question is missing, as are the answer choices.
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if positive integer n is divisible by 5 and 7, then n must also be divisibile by which of the following.?
I. 12
II. 35
III. 70
a. none
b.I only
c. II only
d.I and II
e. II and III
Answer I is out of the question since n is a multiple of 35. However, why is choice III 70 wrong.
QA is C
I. 12
II. 35
III. 70
a. none
b.I only
c. II only
d.I and II
e. II and III
Answer I is out of the question since n is a multiple of 35. However, why is choice III 70 wrong.
QA is C
Appetite for 700 and I scraped my plate!
- Stuart@KaplanGMAT
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Correct!simplyjat wrote:The difference is between CAN BE and MUST BE...
n can be divisible by 70, whereas n must be divisible by 35
You always need to read the question carefully to determine exactly what it is that you're looking for.
If our number is a multiple of 5 and 7, we know it has to be a multiple of 5*7 as well (since they're both primes). Therefore, the minimum value of n is 35.
n could be any other multiple of 35, but since that's not what the question is asking, only II is a MUST be true: choose (c).
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