7
Q:
A) 85 min | B) 95 min |
C) 105 min | D) 100 min |
Answer: D) 100 min
Explanation:
Explanation:
Work done by the third pipe in 1 min = 1/50 - (1/60 + 1/75) = - 1/100.
[-ve sign means emptying]
The third pipe alone can empty the cistern in 100 min.