Question

2 men and 3 boys can do a piece of work in 10 days while 3 men and 2 boys can do the same work in 15 days. In how many days can 1 man and 1 boy do the work?

Answer 1

Here I will use the concept of

Man*Days

(2m+3b) 10 = (3m+2b) 8 

20m+30b = 24m+16b

14b = 4m

7b = 2m

So 2m = 7b

Now

(2m+3b) 10 = (2m+1b) x 

(7b+3b) 10 = (7b+1b) x 

10*10 = 8*x 

X = 100/8

X = 12.5 days