marbles

This topic has expert replies
Master | Next Rank: 500 Posts
Posts: 260
Joined: Sun Oct 12, 2008 8:10 pm
Thanked: 4 times

marbles

by PAB2706 » Mon Mar 23, 2009 11:13 am
Bag A contains red, white and blue marbles such that the red to white marble ratio is 1:3 and the white to blue marble ratio is 2:3. Bag B contains red and white marbles in the ratio of 1:4. Together, the two bags contain 30 white marbles. How many red marbles could be in bag A?
Source: — Problem Solving |

User avatar
Legendary Member
Posts: 2134
Joined: Mon Oct 20, 2008 11:26 pm
Thanked: 237 times
Followed by:25 members
GMAT Score:730

Re: marbles

by logitech » Mon Mar 23, 2009 1:06 pm
BAG A

R/W=1/3=2/6
W/B=2/3=6/9

R/W/B=2/6/9=y

BAG B

R/W=1/4=x

6y+4x=30 --> 3y+2x=15

The two x:y pair would be (3:3) and (6:1)

How many red marbles could be in bag A?

y is either 1 or 3 so the answer is 6 or 18
Last edited by logitech on Mon Mar 23, 2009 1:27 pm, edited 1 time in total.
LGTCH
---------------------
"DON'T LET ANYONE STEAL YOUR DREAM!"

Master | Next Rank: 500 Posts
Posts: 131
Joined: Wed Feb 25, 2009 7:02 am
Location: Azerbaijan/Baku
Thanked: 2 times

by S0laris » Mon Mar 23, 2009 1:06 pm