Question

Working together, A and B can complete a piece of work in 12 days, B and C can complete the same piece of work in
15 days. If A is as twice efficient as C, then the time taken by B alone to complete the same piece of work is:​

Answer 1

Answer:

time taken by b is x

a+x=12

2a+x=15

2a+x=12+3

a=3

3+x=12

6+x=15

x=9

time taken by b is 9days