Question

6 pipes can fill a tank in 24 minutes. One pipe can fill it in 

A. 4 minutes 

B. 30 minutes 

C. 72 minutes 

D. 144 minutes

Answer 1

It is an inverse proportion. 

If 6 pipes can do it in 24 minutes 

Then time taken by 1 pipe = 24 × 6 = 144 minutes