Question

1. A can do a piece of work in 15 days and B can do the same work in 18 days. How many days will they taketo finish the same work together​

Answer 1

Answer:

6 days

Step-by-step explanation:

A takes 15days ….B takes 18 days..

So let us assume workdone to be 90work(LCM of 15,18)

Efficiency of A = 6( work done= efficiency×time)

Efficiency of B = 5

A worked for 10days ie 10×6 ,60 work is done .

Remaining work = 90 work -60 work= 30work.

B alone can complete 30 work in 30/5 = 6 days

Answer 2

Step-by-step explanation:

Time taken by A to do the work=15 days

Time taken by B to do the work=18 days

Work done by A in 1 day=1/15

Work done by B in 1 day=1/18

So,work done by A and B in one day=1)15+1/18=6/90+5/90=(6+5)/90=11/90

Hence,A and B can do the piece of work in 90/11 days .