Question

three men a B and c can do a piece of work in 9 hours 18 hours and 12 hours respectively how long will they take if they work together​

Answer 1

Answer:

let total work be 1 or 100%

if A can do 1 or 100% work in 9 hrs

9hrs= 1 work so.(simple unitary method)

A one hr work=1/9

B one hr work=1/18

C one hr work=1/12

work done by all three in one hr=1/9+1/18+1/12

=(4+2+3)/36=9/36=1/4

if 1/4 work in 1 hr

so one work in 4 hr.

so together they can do work in 4 hrs

Answer 2

Answer:

let the total work be 100