Question

two men can do a piece of work in 6 hours and 4 hours respectively .after the first has worked for 2 hours he is joined by the other. by when should the work be completed ?

Answer 1

8 hours I hope you helped this answer

Answer 2

Answer:

1.6 hours

Step-by-step explanation:

Let the two men be A and B

A can do a piece of work in 6 hours

So, A can do work in  1 hour = $\frac{1}{6}$

B can do a piece of work in 4 hours

So,B can do work in  1 hour = $\frac{1}{4}$

Together they can do work in hour =  $\frac{1}{6}+\frac{1}{4}$

                                                            =  $\frac{5}{12}$

A can do a part of work in 2 hours =  $\frac{2}{6}$

Remaining work = $1-\frac{2}{6}=\frac{4}{6}$

They can do  $\frac{5}{12}$ work together in 1 hour

So, They can do  $\frac{4}{6}$ work together =$\frac{\frac{4}{6}}{\frac{5}{12}}$

                                                                                     =$1.6 hours$