Question

40 men can cut 60 trees in 8 hours , if 8 men leave the jobs how many trees will cut in 12 hours?

Answer 1

40 men can cut 60 trees in 8 hours
1 men can cut 60/40 trees in 8 hours
40-8
=32 men can cut 60×32/40 trees in 8 hours
32 men can cut 60×32/(40×8) trees in 1 hours
32 men can cut in 12 hours 60×32×12/(40×8)=72 trees.

Answer 2

72 trees cut by 32 men in 12 hours  

Given :

40 men can cut 60 trees in 8 hours

To find :  

No of trees cut by 32 men in 12 hours

Solution :  

40 men can cut 60 trees in 8 hours

No of trees cut by 1 man in 8 hours $=\frac{60}{40}$

If 8 men leaves the job then the total men available for work is 32

No of trees cut by 32 men in 8 hours $=\frac{60}{40} \times 32$

No of trees cut by 32 men in 1 hour $=\frac{60 \times 32}{40 \times 8}$

No of trees cut by 32 men in 12 hours $=\frac{60 \times 32}{40 \times 8} \times 12$

No of trees cut by 32 men in 12 hours = 72  

Therefore, in 12 hours 32 men will cut 72 trees.