Question

Dorothy and Rosanne are baking cookies for a party. Working alone, Rosanne can finish the cookies in 6 hours. Dorothy can finish them in 8 hours if she works alone. How long will it take them to bake the cookies if they are working together? Round your answer to the nearest hundredth if necessary.

7.00hours

3.43hours

0.29hours

14.00hours

Answer 1

Well you would have them work together which can possibly cut the work time in half. So if you have them both working then it can speed up the process to B. I hope this helped :D

Answer 2

Option 3.43 hours

Explanation:

Dorothy and Rosanne are baking cookies for a party. Rosanne alone can finish the cookies in 6 hours.

So per hour work done by Rosanne will be =
`(1)/(6)`

Dorothy can finish the cookies in 8 hours, so per hour work done by Dorothy =
`(1)/(8)`

So per hour work done by both Dorothy and Rosanne =
`(1)/(6)+(1)/(8)=(7)/(24)`

Therefore total time taken by Dorothy and Rosanne =
`(24)/(7)=3.43`

Both will finish the work in 3.43 hours.

Option B. 3.43 hours is the correct option.