Question

A and b together can do a piece of work in 12 days which b and c together can do in 16 days. after a has been working at it for 5 days and b for 7 days, c finishes it in 13 days. in how many days b could finish the work

Answer 1

a+b work one day = 1/12

b+ c work =1/16

c has work = x

a has been work done 5 days + b has been work done7 day + c has work done 13 day = 1

work done by a and b 5 day+ b and c done 2 day + work done by c 11 day =1

5/12+2/16+11x=1

5/12+1/8+11x=1
13/24+11x =1

11x =11/24

x = 1/24

c work in completed 24 day