Problema Solution
Mathew can cut the grass in 4 hours working by himself. When Mathew cuts the grass with his younger brother Michael, it takes 3 hours. How long would it take Michael to cut the grass if he worked by himself?
Answer provided by our tutors
Let 'x' represent the number of hours that Michael needs to cut the grass by himself.
Michael's rate is 1/x of the job per hour.
Mathew's rate is 1/4 of the job per hour.
The together rate is 1/3 of the job per hour.
Now we can write:
1/x + 1/4 = 1/3
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click here to see the equation solved for x
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x = 12 hr
Michael will need 12 hours to finish the work by himself.