Question

A can do a job in 20 days B in 30 days and C in 60 days. if A is helped by B and C on every third day then in how many days will the job be finished
plz solve this question step by step ​

Answer 1

Let's see so

A can do work in 20 days

So work done in 1 day=1/20

same goes for B's 1 day work=1/30

and C's 1 day work=1/60

on every third day,

work done=1/20+1/30+1/60=3+2+1/60=6/60=1/10

as all A,B and C are working that day so their one day work is going to be add every third day and else days only 1/20 is done which is work done by A in a day.

So 1/10=2/20(multiplied by 2)

now 1/20 work in 2 days then third day 2/20 work done likewise if you count so

1/20+1/20+2/20+1/20+1/20+2/20+1/20+1/20+2/20+1/20+1/20+2/20+1/20+1/20+2/20=20/20=1 job finished

so total days=15 days answer

Hope it helps