SOLUTION: It takes sally 15 minutes to pick apples from the tree in her backyard. Lisa can do it in 25 minutes. How long will it take them together?

Algebra ->  Rate-of-work-word-problems -> SOLUTION: It takes sally 15 minutes to pick apples from the tree in her backyard. Lisa can do it in 25 minutes. How long will it take them together?      Log On


   

Question 352889: It takes sally 15 minutes to pick apples from the tree in her backyard. Lisa can do it in 25 minutes. How long will it take them together?
Found 2 solutions by scott8148, amalm06:
Answer by scott8148(6628) About Me  (Show Source):
You can put this solution on YOUR website!
(x / 15) + (x / 25) = 1

Answer by amalm06(224) About Me  (Show Source):
You can put this solution on YOUR website!
Work rate, Sarah: dWs/dt=1/15 --> dWs=(1/15)dt

Work rate, Lisa: dWL/dt=1/25 --> dWL=(1/25)dt

W=int%28+%281%2F15%29%2B%281%2F25%29%2C+dt%2C+0%2C+t%29%29=1

[(1/15)+(1/25)]t=1

t=9.375 hrs (Answer)