When a certain number X is divided by 63, the remainder is 27. What is the remainder when X is divided by 7?
A. 2
B. 3
C. 4
D. 5
E. 6
The OA is E.
If, X / 63, the remainder is 27.
I can write, 63 = 9*7
Now, X / 7, what is the remainder?
I'm a little confused by this PS question. Experts, any suggestion about how o solve it? Thanks in advance.
5-Day Free Trial
5-day free, full-access trial TTP
Available with Beat the GMAT members only code
MORE DETAILS
When a certain number X is divided 63, the remainder...
This topic has expert replies
-
BTGmoderatorLU
- Moderator
- Posts: 2209
- Joined: Sun Oct 15, 2017 1:50 pm
- Followed by:6 members
GMAT/MBA Expert
-
Brent@GMATPrepNow
- GMAT Instructor
- Posts: 16207
- Joined: Mon Dec 08, 2008 6:26 pm
- Location: Vancouver, BC
- Thanked: 5254 times
- Followed by:1268 members
- GMAT Score:770
When it comes to remainders, we have a nice rule that says:LUANDATO wrote:When a certain number X is divided by 63, the remainder is 27. What is the remainder when X is divided by 7?
A. 2
B. 3
C. 4
D. 5
E. 6
If N divided by D leaves remainder R, then the possible values of N are R, R+D, R+2D, R+3D,. . . etc.
For example, if k divided by 5 leaves a remainder of 1, then the possible values of k are: 1, 1+5, 1+(2)(5), 1+(3)(5), 1+(4)(5), . . . etc.
When a certain number X is divided by 63, the remainder is 27
So, some possible values of X are: 27, 27+63, 27+(2)(63), 27+(3)(63), . . . etc
The easiest number to work with is the smallest, 27.
So, let's see what happens when X = 27
What is the remainder when X is divided by 7?
27 divided by 7 equals 3 with remainder 6
Answer: E
Cheers,
Brent
Brent Hanneson - Creator of GMATPrepNow.com
