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# Working Machines

Author Message
TAGS:
Manager
Joined: 22 Jul 2008
Posts: 95
Location: Bangalore,Karnataka
Followers: 3

Kudos [?]: 78 [0], given: 11

Working Machines [#permalink]  30 Nov 2009, 06:57
00:00

Difficulty:

(N/A)

Question Stats:

67% (05:32) correct 33% (02:11) wrong based on 16 sessions
I guess a similar question was posted by Bunuel sometime back.. anyhow here it is

(A) 12 minutes
(B) 15 minutes
(C) 18 minutes
(D) 36 minutes
(E) 54 minutes

Last edited by kirankp on 30 Nov 2009, 08:01, edited 1 time in total.
VP
Joined: 05 Mar 2008
Posts: 1473
Followers: 11

Kudos [?]: 216 [0], given: 31

Re: Working Machines [#permalink]  30 Nov 2009, 07:18
kirankp wrote:
I guess a similar question was posted by Bunel sometime back.. anyhow here it is

(A) 12 minutes
(B) 15 minutes
(C) 18 minutes
(D) 36 minutes
(E) 54 minutes

A and B together = 1/a + 1/b = 1/6

B and C together = 1/b + 1/c = 1/9

We need to know the answer to 1/a - 1/c

From equation 2: 1/b = 1/9 - 1/c
substitute into equation 1

1/a + 1/9 - 1/c = 1/6
1/a - 1/c = 1/18

18 minutes
Re: Working Machines   [#permalink] 30 Nov 2009, 07:18
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