Question

A certain number of men can finish a piece of work in 80 days. If however,
there were 8 men less, it would take 20 days more to complete the work. How
many men were there originally ?

Answer 1

Answer:

Let the original number of men=x.

So, x men finish the work in100days.

After 10 men leave,

x−10 men finish the work in (100+10)=110days.

Now the number of men is inversely proprtional to the number of days

in which they finish the work.

∴

x−10

x = 100110

⟹100x=110x−1100

⟹x=110.

So the original number of men was 110.