Question

100 carpenters complete 20 Windows in a week how many carpenter's complete the same number in 21 days

Answer 1

If 100 can do this in 7 days

So 21 days = 100*3
= 300 carpenters

Answer 2

A week contains 7 days
no.of days required to complete the work=21

21/7=3
100 carpenter can complete it in 20 days
100*3=300
300 Carpenters are needed to complete the work in 21 days