Find all School-related info fast with the new School-Specific MBA Forum

 It is currently 18 May 2013, 09:37

Alligation Problem

Author Message
TAGS:
Intern
Joined: 22 Jan 2011
Posts: 8
Followers: 0

Kudos [?]: 0 [0], given: 0

Alligation Problem [#permalink]  22 Jan 2011, 03:22
00:00

Question Stats:

33% (02:59) correct 66% (00:51) wrong based on 0 sessions
A container has a capacity of 200 gallons and is full of spirit. 4 gallons of spirit is drawn out and the container is again filled with water. This process is repeated 5 times. Find how much spirit is left in the resulting mixture finally?

a) 6(257/525) gallons b) 6(346/625) gallons

c) 6.5 gallons d)6.25 gallons

e) None of these

Please solve through alligation or short cut process....
[Reveal] Spoiler: OA
GMAT Club team member
Joined: 02 Sep 2009
Posts: 11506
Followers: 1791

Kudos [?]: 9519 [1] , given: 826

Re: Alligation Problem [#permalink]  22 Jan 2011, 10:43
1
KUDOS
sonuindia88 wrote:
A container has a capacity of 200 gallons and is full of spirit. 4 gallons of spirit is drawn out and the container is again filled with water. This process is repeated 5 times. Find how much spirit is left in the resulting mixture finally?

a) 6(257/525) gallons
b) 6(346/625) gallons
c) 6.5 gallons
d) 6.25 gallons
e) None of these

First of all I think it should be 20 gallons instead of 200 in order the answer to be B.

Note that 4 gallons is 20% of a capacity. Now, when we remove 20% of spirit for the first time 80% of spirit is left --> when we remove 4 gallons of the mixture for the second time, or again 20% of the capacity, we still remove 20% of the remaining spirit with it (this 4 gallons of the mixture, which is 20% of the capacity, contains 20% of the remaining spirit), so again 80% of the spirit is left... So every time we remove 4 gallons, we re move 20% of the remaining spirit and 80% is left. So after 5 removals there will be 20*0.8^5 gallons of spirit left: 20*(\frac{4}{5})^5=\frac{4^6}{5^4}= 6\frac{346}{625}.

Similar questions:
eight-litres-are-drawn-off-from-a-vessel-full-of-water-and-s-95749.html
problem-solving-97300.html
_________________
Re: Alligation Problem   [#permalink] 22 Jan 2011, 10:43
Similar topics Replies Last post
Similar
Topics:
1 Alligators from sets 3 22 May 2008, 13:38
1 mix and alligation 2 16 Dec 2009, 03:18
2 Alligation problem 9 05 Feb 2011, 11:11
Are Alligation and Mixture problems part of GMAT Quant ? 2 11 Jul 2011, 09:00
QUESTION OF ALLIGATION .. 1 24 Sep 2011, 12:43
Display posts from previous: Sort by