Time And Work Ques 21
Question-
The respective ratio of the time taken by $A$ and $B$ individually to finish a piece of work is $5: 4$. The respective ratio of the time taken by $B$ and $C$ individually to finish the same piece of work is $4: 3$. If $A$ and $C$ together can finish the same piece of work in $11 \frac{1}{4}$ days, in how many days can $B$ alone finish the same piece of work?
(1) 28
(2) 16
(3) 20
(4) 32
(5) 24
(IBPS RRBs Officers CWE (Prelim Exam) 09.09.2017 IInd Sitting)
Show Answer
Correct Answer: (5)
Solution: (5)
Ratio of the time taken by each of $A, B$ and $C$ in doing 1 work $=5$ $: 4: 3$
Time taken by $A=5 x$ days
Time taken by $C=3 x$ days
According to the question,
$ \begin{aligned} & \frac{1}{5 x}+\frac{1}{3 x}=\frac{4}{45} \\ \Rightarrow & \frac{3+5}{15 x}=\frac{4}{45} \end{aligned} $
$\Rightarrow \frac{8}{x}=\frac{4}{3}$
$\Rightarrow 4 x=8 \times 3$
$\Rightarrow x=\frac{8 \times 3}{4}=6$
$\therefore$ Time taken by $B=6 \times 4$ $=24$ days
BETA
