$8$ pipes can fill a tank in $27$ hours. How long would $12$ pipes (of the same kind) take to fill it?

$8$ pipes can fill a tank in $27$ hours. How long would $12$ pipes (of the same kind) take to fill it?
  1. $15$ hr
  2. $18$ hr
  3. $20$ hr
  4. $24$ hr

Solution

$8 \times 27 = 12 \times t \Rightarrow t = \dfrac{216}{12} = 18$ hr.

Asked in: IMO

Practice more DIRECT AND INVERSE PROPORTIONS questions on Aicharya