Question

Tim and Jim are working on a school project together. If he had to work by himself, it would take

Tim 10 hours to complete the school project. If Jim worked alone, it would take him 15 hours.
Working together, how long will it take Tim and Jim to complete the school project together?

Answer 1

Answer: 6 hours

Explanation:

Given, Tim and Jim are working on a school project together.

Tim takes 10 hours to complete the school project.

If Jim worked alone, it would take him 15 hours

Let t be the time they both take if they work together.

Then,
`(1)/(t)=\frac{1}{\text{Time taken by Tim}}+\frac{1}{\text{Time taken by jim}}`

`\Rightarrow\ (1)/(t)=(1)/(10)+(1)/(15)\\\\\Rightarrow\ (1)/(t)=(3+2)/(30)=(5)/(30)\\\\\Rightarrow(1)/(t)=(1)/(6)\\\\\Rightarrow t=6`

So, it will take 6 hours to complete the school project together .