Question

If 9 men can do a work in 18 days, how many days will 3 men require to complete the same work, if they are working double that time?

Answer 1

9 men can do a work in 18 days

Here as men increases ; number of days to complete the work decreases or as men decreases ; number of days to complete the work increases, which means it is an indirect proportion. Then

1 men can do a work in 162(18×9) days

It is said 3 men is working at double that time which is equivalent to 6 men work ;

3 men working at double time can do a work in 162÷(3×2) = 27 days