Which is greater than 2/3?

A) 33/50

B) 8/11

C) 3/5

D) 13/17

E) 5/8

The answer is B. Is there a quick way to do this? Benchmarking didn't work for me but maybe I approached it wrong. The multiplication method seemed to take too long.

Cross multiplication is fastest, in case of small numbers like this.


I went with option (A) first 2/3 and 33/50, 100(50 * 2) and 99 (33 * 3).
But you are right, if the right answer would have been (E) , i would have to do 5 multiplications.

2/3 ~ 0.67,

Options A, C & E are all less than 0.67 while both B & D are greater than 0.67...

B) 8/11~ 0.73

D) 13/17~ 0.76

MGMAT staff your suggestions please...

The question is wrong. D is also right as 13/17 = 0.764 which is > 2/3.

Assuming that's a typo, the other numbers can be eliminated quickly with some logic:

33/50 -> 50 is half of 100, so double the top to get 66%. 2/3 is 66.66%.
8/11 -> One third of 12 is 4, so 8/12 is 2/3 and 8/11 is therefore > 2/3.
3/5 -> this is the same as 60%, which is < 2/3.
13/17 -> one third of 18 is 6, so 12/18 is 2/3 and 13/17 is > 2/3.
5/8 -> one third of 9 is 3, so 6/9 is 2/3 and therefore 5/8 is not going be > 2/3.

choice (d) is supposed to be 13/27. this value is less than 1/2, so it's not even close to 2/3.
that should clear up any doubts about this problem.