Asked by john
Amy can clean the house in 7 hours. When she works together with Tom, the job takes 5 hours. How long would it take Tom, working by himself, to clean the house?
Answers
Answered by
Reiny
Amy's rate = house/7
Tom's rate = house/x
combined rate = house/7 + house/x
= (xhouse + 7house)/(7x)
= house(x+7)/(7x)
then
house/[house(x+7)/(7x) = 5
1/[(x+7)/(7x)] = 5
7x/(x+7) = 5
7x = 5x+35
2x=35
x = 35/2 or 17.5 hours
check:
combined rate = 1/17.5 + 1/7 = 2/35 + 1/7 = 1/5
time = 1/(1/5) = 5
Tom's rate = house/x
combined rate = house/7 + house/x
= (xhouse + 7house)/(7x)
= house(x+7)/(7x)
then
house/[house(x+7)/(7x) = 5
1/[(x+7)/(7x)] = 5
7x/(x+7) = 5
7x = 5x+35
2x=35
x = 35/2 or 17.5 hours
check:
combined rate = 1/17.5 + 1/7 = 2/35 + 1/7 = 1/5
time = 1/(1/5) = 5
Answered by
Tad
Can someone explain What percentage of the work did each person do?
Answered by
ooh ooh a a a lllllaaaa
Stop cheating on thinkwell !!
There are no AI answers yet. The ability to request AI answers is coming soon!
Submit Your Answer
We prioritize human answers over AI answers.
If you are human, and you can answer this question, please submit your answer.