Question

A, B and C can complete a work separately in
24, 36 and 48 days respectively. They started
together but C left after 4 days of start and A
left 3 days before the completion of the work.
In how many days will the work be completed?
(a) 15 days (b) 24 days
(c) 25 days (d) 38 days

Answer 1

(A + B + C)'s 1 day's work = (1/24+1/36+1/48)=13/144

Work done by (A + B + C) in 4 days = 4*13/144=13/36

Work done by B in 3 days = 1/36?3=1/12

Left work = [1?(13/36+1/12)]=5/9

(A + B)'s 1 day's work = (1/24+1/36)=5/72

5/72 part of work is done by A and B = 1 day

5/9 work done by A & B = (72/5?5/9) = 8 days.

So, total time taken = (4 + 3 + 8) days = 15 days.

Answer 2

Answer:15 days

Step-by-step explanation:

(A + B + C)'s 1 day's work = (1/24+1/36+1/48)=13/144

Work done by (A + B + C) in 4 days = 4*13/144=13/36

Work done by B in 3 days = 1/36*3=1/12

Left work = [1-(13/36+1/12)]=5/9

(A + B)'s 1 day's work = (1/24+1/36)=5/72

5/72 part of work is done by A and B = 1 day

5/9 work done by A & B = (72/5*5/9) = 8 days.

So, total time taken = (4 + 3 + 8) days = 15 days.