Answers

  • Brainly User
2014-03-25T21:25:41+05:30
Let a,b and c can do 1/A,1/B and 1/C of the work in each day 

 \frac{1}{A} + \frac{1}{B} = \frac{1}{10} ....(1)
\frac{1}{B} + \frac{1}{C} = \frac{1}{15}......(2)
\frac{1}{A} + \frac{1}{C} = \frac{1}{18}.......(3)
subtract (1) and (2)
\frac{1}{A} - \frac{1}{C} = \frac{1}{10}- \frac{1}{15}=\frac{1}{30}.....(4)
 add (4) and (3)
\frac{2}{A}  = \frac{4}{45}
so A can do it 22.5 days
similarly B can do it 18 days
and C can do it  90 days

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