If a and b are odd integers such that a - b > 7, what is the smallest possible positive difference between a and an even number less than b?
A) 7
B) 8
C) 9
D) 10
E) 11
OA:C
If a and b are odd integers such that a - b > 7,
This topic has expert replies
- melguy
- Master | Next Rank: 500 Posts
- Posts: 335
- Joined: Mon Mar 21, 2011 11:31 pm
- Location: Australia / India
- Thanked: 37 times
- Followed by:2 members
We are starting from 1 as we want the lowest possible value. But the option is red is not possible as we need to have an even number less than B.
The next option after that is A = 11 B = 3
So 11 - 2(an even integer less than B) = 9
Answer is C
The next option after that is A = 11 B = 3
So 11 - 2(an even integer less than B) = 9
Answer is C
- Attachments
-
- DavidG@VeritasPrep
- Legendary Member
- Posts: 2663
- Joined: Wed Jan 14, 2015 8:25 am
- Location: Boston, MA
- Thanked: 1153 times
- Followed by:128 members
- GMAT Score:770
You can also a little logic and the answer choices. If a is ODD and we subtract an EVEN, we'll get an ODD result. (ODD - EVEN = ODD.) So we know the answer is odd. Eliminate B and D. We know that a - b > 7, so if we were to subtract a number smaller than b, the difference would have to be even bigger than 7. Eliminate A. So we just want the smallest odd remaining, which would be C, 9.NandishSS wrote:If a and b are odd integers such that a - b > 7, what is the smallest possible positive difference between a and an even number less than b?
A) 7
B) 8
C) 9
D) 10
E) 11
OA:C
-
- GMAT Instructor
- Posts: 2630
- Joined: Wed Sep 12, 2012 3:32 pm
- Location: East Bay all the way
- Thanked: 625 times
- Followed by:119 members
- GMAT Score:780
Let's say that c is the nearest even number to b that is less than b.
Then we know c = b - 1.
We want a - c.
Since a - b > 7, the smallest possible value of (a - b) = 8.
Since c = (b - 1), the smallest possible value of a - c = (a - (b - 1)) = (a - b) + 1 = 9.
Then we know c = b - 1.
We want a - c.
Since a - b > 7, the smallest possible value of (a - b) = 8.
Since c = (b - 1), the smallest possible value of a - c = (a - (b - 1)) = (a - b) + 1 = 9.