Miscellaneous Question 74
- If pipes $A$ and $B$ can fill a tank in 15 minutes and 20 minutes respectively and pipe $C$ can empty the full tank in 12 minutes, what will be the time taken by $A$, $B$ and $C$ together to fill the tank completely?
(1) 25 minutes
(2) 30 minutes
(3) 40 minutes
(4) 20 minutes
(5) 35 minutes
IBPS RRBs Officer CWE (Prelim Exam) 04.08.2019
Show Answer
Correct Answer: 74. (2)
Solution: 74. (2) Part of tank filled by pipes A, $\mathrm{B}$ and $\mathrm{C}$ in 1 minute
$=\frac{1}{15}+\frac{1}{20}-\frac{1}{12}$
$=\frac{4+3-5}{60}=\frac{2}{60}=\frac{1}{30}$
$\therefore$ Required time $=30$ minutes
BETA
