Question

if a takes 4/5 days as b takes and working together they require 20/3 days to complete the whole work.what is the efficiency of b?

Answer 1

Answer:

80%

Step-by-step explanation:

Given if a takes 4/5 days as b takes and working together they require 20/3 days to complete the whole work.what is the efficiency of b?

Let B take x days to complete work. So A will take 4/5 x days to complete the work.

Now A's work in one day is 5/4 x

 B's one day work will be = 1/x

So the work done by A + B in one day = 3/20

 5/4x + 1/x = 3/20

 9/4x = 3/20

12 x = 180

 x = 15 days

 a = 4/5 x = 4 x 15/ 3 = 12

Now to calculate efficiency,

b = 12 x 100/15 = 80

so efficiency of b = 80%

Answer 2

Answer:

6 2/3%

Step-by-step explanation:

efficiency of A+B=100/(20/3)=15%

A. B.

no. of days 4. 5

efficiency. 5. 4

efficiency of B =4/9*15

=20/3

=6 2/3%