Question

A does 75% of a work in 25days. After that Z joined and they together finish the remaining work in 5 days. In how many days Z can complete the whole work alone?​

Answer 1

Z alone will take 50 days to complete the work

Answer 2

Z can complete the whole work in 50 days

Let the total work be equal to x

Work done by A in 25 days = 75x/100

= 0.75x

Work done by A in one day = 0.75x/25

Let one day work of Z = y

Work done by A and Z in 5 days = 0.25x

=> Five day work of A + five day work of Z = 0.25x

=> 0.75x/25 × 5 + 5 × y = 0.25x

=> 5y = 0.1x

=> y = 0.1x/5

Time taken by Z to complete the work alone

=> One day work × no. of days = total work

=> 0.1x/5 ×t = x

=> t = 50 days