Question

Narendra can copy 50 pages in 10 hrs.Narenda and Prasad together can copy 300 pages in 40 hours. In how much time prasad can copy 30 pages.

Answer 1

Narendra can copy 50 pages in 10 hours.

That means in 40 hours he can copy 50×4=200 pages.

Narendra and prasad together can copy 300pages in 40 hours.

That means prasad alone can copy 300-200=100 pages in 40 hours.

So to copy 30 pages prasad

will take 40/100 ×30 = 12 hours.

Hope you understand and it helps.