SOLUTION: Christopher can paint the interior of his house in 14 hours. If he hires Cynthia to help him, they can do the same job together in 10 hours. If he lets Cynthia work alone, how long

Algebra ->  Rate-of-work-word-problems -> SOLUTION: Christopher can paint the interior of his house in 14 hours. If he hires Cynthia to help him, they can do the same job together in 10 hours. If he lets Cynthia work alone, how long      Log On


   

Question 636747: Christopher can paint the interior of his house in 14 hours. If he hires Cynthia to help him, they can do the same job together in 10 hours. If he lets Cynthia work alone, how long will it take her to paint the interior of his house?
Answer by jerryguo41(197) About Me  (Show Source):
You can put this solution on YOUR website!
1. Write the equation for painting the house with both people
10*Rate of Chris + 10*Rate of Cynthia = 1 Painted house
2. Write known and Unknown variables:
Rate of Chris: 1/14 per hour
Rate of Cynthia: x
10*Rate of Chris + 10*Rate of Cynthia = 1 Painted house
10%2A%281%2F14%29%2B10x=1
%2810%2F14%29%2B10x=1
10x=1-%2810%2F14%29
x=1%2F35
Cynthia would have taken 35 hours to paint the house on her own.