Probability

Expert replies

tsmith93: Senior | Next Rank: 100 Posts; Posts: 32; Joined: Fri Feb 19, 2010 12:36 pm; Location: Pennsylvania; Thanked: 1 times

by tsmith93 » Sun Feb 21, 2010 3:58 pm

Jason has twice as many red marbles as blue marbles. He puts them in two jars in such a way that the ratio of the number of red marbles to blue marbles in jar I is 2:7 and there are only red marbles in jar II. The number of red marbles in jar II is how many times the number of red marbles in jar I?

Like this post

Source: Beat The GMAT — Problem Solving | Sun Feb 21, 2010 3:58 pm

harsh.champ: Legendary Member; Posts: 1132; Joined: Mon Jul 20, 2009 3:38 amFollowed by: 6 members; Location: India; Thanked: 64 times; GMAT Score:760

by harsh.champ » Sun Feb 21, 2010 4:16 pm

tsmith93 wrote:Jason has twice as many red marbles as blue marbles. He puts them in two jars in such a way that the ratio of the number of red marbles to blue marbles in jar I is 2:7 and there are only red marbles in jar II. The number of red marbles in jar II is how many times the number of red marbles in jar I?

R=2 x B
In Jar 1,ratio R:Bis 2:7, in jar II there are only red marbles
so in jar 2 we have all the blue marbles i.e. B and some red marbles its no. 2/7 B
Let it be 2x and 7x
and y
2x + y= 14x
Hence,y=12x
so, we have y/2x = 12x/2x =6:1

Last edited by harsh.champ on Sun Feb 21, 2010 4:26 pm, edited 2 times in total.

It takes time and effort to explain, so if my comment helped you please press Thanks button

Just because something is hard doesn't mean you shouldn't try,it means you should just try harder.

"Keep Walking" - Johnny Walker

Like this post

shashank.ism: Legendary Member; Posts: 1022; Joined: Mon Jul 20, 2009 11:49 pmFollowed by: 2 members; Location: Gandhinagar; Thanked: 41 times

by shashank.ism » Sun Feb 21, 2010 4:20 pm

tsmith93 wrote:Jason has twice as many red marbles as blue marbles. He puts them in two jars in such a way that the ratio of the number of red marbles to blue marbles in jar I is 2:7 and there are only red marbles in jar II. The number of red marbles in jar II is how many times the number of red marbles in jar I?

so R = 2 B
ratio R:B in jar I is 2:7, in jar II there are only red marbles
so in jar 2 we have all the blue marbles i.e. B and some red marbles its no. 2/7 B
in jar II red marbles = 2B- 2/7 B = 12/7 B
so jar II /jar I = [12/7 B]/[2/7 B] = [spoiler]6 ans
[/spoiler]

My Websites:
www.mba.webmaggu.com - India's social Network for MBA Aspirants

www.deal.webmaggu.com -India's online discount, coupon, free stuff informer.

www.dictionary.webmaggu.com - A compact free online dictionary with images.

Nothing is Impossible, even Impossible says I'm possible.

Like this post

thephoenix: Legendary Member; Posts: 1560; Joined: Tue Nov 17, 2009 2:38 amFollowed by: 5 members; Thanked: 137 times

by thephoenix » Sun Feb 21, 2010 5:15 pm

tsmith93 wrote:Jason has twice as many red marbles as blue marbles. He puts them in two jars in such a way that the ratio of the number of red marbles to blue marbles in jar I is 2:7 and there are only red marbles in jar II. The number of red marbles in jar II is how many times the number of red marbles in jar I?

let the # of blue marbles=x
so # of red marbles=2x

now let # of red marbles in jar2=z

so # of red marbles in jar1=2x-z

ratio=(2x-z)/x=2/7-------->z=12x/7
so # of red marbles in jar1=2x-(12x/7)=2x/7............say z1

so z=n(z1) i.e n times of # of red marbles in z1
----->n=z/z1=12x/7/2x/7=6 is the ans

Like this post

Post new topic Post Reply

• Page 1 of 1

GMAT Course Reviews

560 reviews

1168 reviews

431 reviews

359 reviews

147 reviews

5/5

5 Star (560 Reviews)

"Target Test Prep is the closest to the official version of the GMAT exam, about 99% accuracy in terms of the quality and quantity of information. The course has excellently created singular sets of focused lessons and tests for every possible topic that one could come across in the official GMAT exam."

"The TTP course maximizes the efficiency of the time you spend studying. It will take time and effort but I could almost guarantee that if you complete the course exactly as it is laid out you will get an amazing score. They also have a very responsive team willing to help with any questions you might have."

"TTP has two things that I think no other test prep company offers: A teaching approach that reinforces understanding and an attitude that will give you the mental preparedness needed to succeed on the test. TTP gives you a deep understanding of the concept you need to know while teaching you how to think."

Write a Review