x/y?

This topic has expert replies
Master | Next Rank: 500 Posts
Posts: 265
Joined: Tue Jul 03, 2012 11:04 pm
Followed by:6 members

x/y?

by grandh01 » Thu Aug 23, 2012 2:41 pm
If x (a + b) = y, where y ≠ 0 and 2a
= 3b = 1, then =
y/x
(A)1/6
(B)1/3
(C)2/3
(D)5/6
(E)6/5

Master | Next Rank: 500 Posts
Posts: 392
Joined: Thu Jan 15, 2009 12:52 pm
Location: New Jersey
Thanked: 76 times

by truplayer256 » Thu Aug 23, 2012 5:16 pm
2a = 3b = 1 => a = 1/2 and b = 1/3

x(a + b) = y => y/x = (a + b) = 1/2 + 1/3 = 5/6

Choose D.

Master | Next Rank: 500 Posts
Posts: 435
Joined: Wed Nov 16, 2011 7:27 am
Thanked: 48 times
Followed by:16 members

by alex.gellatly » Thu Aug 23, 2012 7:43 pm
grandh01 wrote:If x (a + b) = y, where y ≠ 0 and 2a
= 3b = 1, then =
y/x
(A)1/6
(B)1/3
(C)2/3
(D)5/6
(E)6/5
2a=3b=1 means that 2a=1 and 3b=1. Solving for them individually we get a=1/2 and b=1/3
If x(a+b)=y; then a+b=y/x since the question is asking for y/x, then simply plug the values we got for a and b into the equation:

1/2 + 1/3 = y/x
5/6= y/x
The correct answer is D
A useful website I found that has every quant OG video explanation:

https://www.beatthegmat.com/useful-websi ... tml#475231