Question

A does 20% wool less than B. If a cap finish
Piece of work in 7/2 hours, B can finish it in.​

Answer 1

Let B's one day work is =1 , then A's one day work= 1 - 20%of 1 = 4/5 work.

Again let B can do the same work in n days , acordingly:-

Work done by B in n days = work done by A in 7 1/2 days.

n×1 = (15/2)×(4/5)

n = 6 days. Answer.

Step-by-step explanation:

Let's take efficiencies ratio of A and B .

As A is 20% less efficient if B does 100 units works A will do 80 units of in same time.

Therefore A:B = 80:100 => 4:5

Since efficiency and time are inversely proportional ratios of time taken by A and B to do certain work is 5:4

It is said that A took 7.5 days to complete the work so B will take ( 7.5/5)* 4 days.

i.e 6 days.

Hope you understand, it is simply proportionality concept.