SOLUTION: Mary and Chris, together can clean their house in 2 hours. Mary alone can clean the house in 3 hours and 30 minutes. How long does it take Chris to clean the house working alone?
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-> SOLUTION: Mary and Chris, together can clean their house in 2 hours. Mary alone can clean the house in 3 hours and 30 minutes. How long does it take Chris to clean the house working alone?
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Question 180966This question is from textbook College Algebra
: Mary and Chris, together can clean their house in 2 hours. Mary alone can clean the house in 3 hours and 30 minutes. How long does it take Chris to clean the house working alone? This question is from textbook College Algebra
You can put this solution on YOUR website! Let x=amount of time it takes Chris working alone to clean the house
Chris therefore works at the rate of 1/x house per hour
Mary and Chris working together works at the rate of 1/2 house per hour
Mary alone works at the rate of 1/(3.5) house per hour
Now we are told that:
1/x + 1/(3.5)=1/2 multiply each term by 7x
7+2x=3.5x subtract 2x from each side
7=3.5x-2x
1.5x=7
x=4 2/3 hours------------------amount of time it takes Chris working alone
4 2/3=14/3
3 1/2=7/2
3/14 +2/7=1/2
3/14+4/14=1/2
1/2=1/2
Hope this helps---ptaylor
