Question

A can do a piece of work in 12 hours and B can do it in 8 hours .how long they will take if they work together?

Answer 1

We will solve this using the LCM technique.

A takes 12 hours & B takes 8 hours. So, let the total work be LCM(12,8) = 24 Units

A -> 12 hours = 2Units/hour

B -> 8 hours = 3 Units/hour

A + B = 5 Units/hour

Thus, TOTAL TIME = 24/5= 4.8 Hours (Answer)

Answer 2

Given:

A can do given work in 12 hrs

B can do given work in 8 hrs

To Find:

The time both will take if they work together.

Explanation:

According to the given question

Time taken by A to do given work in 1 hour = 1/12

Time taken by B to do given work in 1 hour = 1/8

Now if both A and B work together for an hour

= (1/12) + (1/8)

= 24/5

Therefore both can complete a given work in 4.8 hours.