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Work on alternate days

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Work on alternate days

by maihuna » Thu May 07, 2009 7:52 am
A B And C can do a piece of work in 11, 20 and 55 days respectively, working alone. How soon the work can be done if A is assisted by B and C on alternate days.

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by scoobydooby » Thu May 07, 2009 8:44 am
i get 8

days when A, B, C work together, 1/11+1/20+1/55=35/220=7/44 work done.
days when A works alone, 1/11 or 4/44 of work done.

so say in 4 days 7/44+4/44+7/44+4/44=22/44=1/2 work done
=>full work done in 4*2=8 days
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by maihuna » Thu May 07, 2009 8:59 am
there is even simpler method to solve it..try algebrically...
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by scoobydooby » Thu May 07, 2009 9:03 am
can shorten it to:

in 2 days: 7/44+4/44=11/44=1/4 work gets done
so in 8 days full work gets done.

cant think, maihuna you go first :)
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