Question

A can do a piece of work in some time b take thrice the time to do the same work if a can cane 15 chairs in one day how many chairs can b cane in a day

Answer 1

Let 1 be the total work. Let x be the proportion of the total work done in a day by B. Then 3x is the proportion of work done in a day by A. So, the total proportion of work done by A and B at the end of 19 days is 4*(3x) + 15*x = 27x. So we have

27x = .75

So, x = .75/27 = 0.02777… (the proportion of work done by B per day)

The proportion of work left to complete is 1 - 0.75 = 0.25. If B does it, the number of days will be 0.25/x = 9 days.

You can check to see if the total work done by A in 4 days (12x) and B in 24 days (24x) is 1 (100% of the job): 12x + 24x = 36x = 36*0.02777… = 1.0

Answer 2

since it is provided that B takes thrice the time taken by A to do the same work
Let time taken by A be x
then time taken by B will be 3x
now A takes 1 day to cane 15 chairs
so time taken by B to cane 15 chairs will be 3*1=3 days.
now no. of chairs canned by B in 1 day= 15/3=5 chairs.