Question

A,B and C can do a piece of work in 10,12 and 15 days respectively .In how many days will they together do it, and how much of the work will be done by each?

Answer 1

Solution :-

Let the work done by A is n then the work done by A in one day is 1/n
Now work done by A = 10
Work done by A in 1 day = 1/10
Similarly work done by B and C in 1 day are 1/12 and 1/15 respectively
Adding all the work done in 1 day of all A, B, C
(A+B+C)'s work in one day = (1/10 + 1/12 + 1/15)
= (6+5+4)/60
= 15/60
If A's 1 day's work =1/n, then A can finish the work in n days
So, all the three together will complete the job in
One day work of all three (1/n)= 15/60
Finishing of work together of all three (n) = 60/15
= 4 days