Data Sufficiency (DS) | Re: If a, b are the integers, is b divisible by 7 ?

Question

Is b divisible by 7 ?

Statement 1

(1) b – 3 = 3a

b = 3a + 3

b = 3(a+1)

b is divisible by 7, if a + 1 is divisible by 7. We don't know that. Hence the statement is not sufficient and we can eliminate A and D.

Statement 2

(2) a – 6 is divisible by 7

Clearly insufficient. We want to find the divisibility of b.

Combined

From statement 1, we want to find if a+1 is divisible by 7.

From statement 2, we know that a - 6 is divisible. Hence a + 1 is divisible by 7. Sufficient.

Option C

Statistics : Posted by gmatophobia • on 28 Nov 2022, 01:30 • Replies 3 • Views 97

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