Question

A and b can do a piece of work in 18 days.B and c can do in 24 days a c in 36 days.In how many days they do it all working together

Answer 1

A and B can do (1/18)th of the work in a day.

B and C can do (1/24)th of the work in a day.

A and C can do (1/36)th of the work in a day.

2A+2B+2C = (1/18)+(1/24)+(1/36)

= (4/72)+(3/72)+(2/72)

= (9/72) or

A+B+C = (9/144) = (1/16)th of the work in a day.

C alone does (1/16)-(1/18) = (18–16)/(16*18) = 2/(16*18) = (1/144)th part of the work in a day. So C, working alone, will complete the work in 144 days