Solve this problem please

Question

Brandon can paint a fence in 12 hours and Elaine can paint the same fence in 11 hours. How long will they take to paint the fence if they work together?

(use involving work to solve)

 

 

 

 

 

 

 

 

( the answer is 5 17/23 hr but i need help to show me step by step on how they get this answer)

Answer 1

Hi Cathryn--

 

The way you get it is to figure out how much each of them can paint in ONE hour.

 

Brandon can do one-twelfth of it in an hour, and Elaine can do one-eleventh in the same hour.

 

Together they can do 1/12 + 1/11 each hour, or 23/132.

 

If the whole fence is 132/132, you need to do 132 ÷ 23 to find out how many hours.

 

That answer is 5 17/23

 

There ya go!

 

I hope this helps.

 

Matt in New York