1)

A can do $\frac{1}{2}$ of work in 5 days. B can do $\frac{3}{5}$ of  the same work in 9 days and C can do $\frac{2}{3}$ of that work in 8 days. In how many days can three of them together do the work?


A) 3

B) 5

C) 6

D) 4

E) 7

Answer:

Option D

Explanation:

$A$ can do 1 work in 10 days

$B$ can do 1 work in $\frac{(9\times 5)}{3}$ = 15 days

$C$ can do 1 work in $\frac{(8\times 3)}{2}$ = 12 days

$A+B+C$ 's 1 day work $=\frac{1}{10}+\frac{1}{15}+\frac{1}{12}$ $=\frac{1}{4}$

They can complete the work in 4 days