BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem

If a positive integer n is divisible by both 5 and 7

Expert replies
by M7MBA » Mon Apr 15, 2019 1:27 am

Timer

00:00

Answers

A

B

C

D

E

Stats

Difficulty

If a positive integer "n" is divisible by both 5 and 7, then "n" must also be divisible 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

[spoiler]OA=C[/spoiler]

Source: Official Guide
Join the discussion
Source: — Problem Solving |

by Scott@TargetTestPrep » Wed Apr 17, 2019 5:46 pm
M7MBA wrote:If a positive integer "n" is divisible by both 5 and 7, then "n" must also be divisible 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

[spoiler]OA=C[/spoiler]

Source: Official Guide

Since n is divisible by both 5 and 7 it MUST be divisible by the least common multiple of 5 and 7, which is 35. If we take n = 35, we see that n is not necessarily divisible neither by 12 nor by 70.

Answer: C

Scott Woodbury-Stewart
Founder and CEO
[email protected]

Image

See why Target Test Prep is rated 5 out of 5 stars on BEAT the GMAT. Read our reviews

ImageImage
Join the discussion