SSC Sample Paper Mock Test-2 SSC CGL Tear-II Paper-1

                 A and B can do given work in 8 days, B and C can do the same work in 12 days and A, B, C complete it in 6 days. In how many days can A and C finish it?

A) 12

B) 8

C) 14

D) 16

Correct Answer: B

Solution :

(A+B)?s 1 day?s work \[=\frac{1}{8}\]

(B+C)?s 1day?s work \[=\frac{1}{12}\]

(C+A)?s1 day?s work\[=\frac{1}{x}\]

\[\therefore \](A+B+C)?s 1 day?s work \[=\frac{1}{2}\left[ \frac{1}{8}+\frac{1}{12}+\frac{1}{x} \right]\]

\[\left( \frac{1}{6} \right)=\frac{1}{2}\left[ \frac{1}{8}+\frac{1}{12} \right]+\frac{1}{2x}\]

\[\Rightarrow \] \[\frac{1}{x}=\frac{1}{3}-\left( \frac{1}{8}+\frac{1}{12} \right)=\frac{3}{24}=\frac{1}{8}\]

So, C and A can do the work in 8 days.