SOLUTION: A man can mow his lawn in 4 hours. His son can do the job in 3 hours. If the son takes over an hour after his father, how long will it take him to finish mowing the lawn?
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-> SOLUTION: A man can mow his lawn in 4 hours. His son can do the job in 3 hours. If the son takes over an hour after his father, how long will it take him to finish mowing the lawn?
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Question 1141930: A man can mow his lawn in 4 hours. His son can do the job in 3 hours. If the son takes over an hour after his father, how long will it take him to finish mowing the lawn? Answer by VFBundy(438) (Show Source):
You can put this solution on YOUR website! Formula for work problems:
Rate of work * Time spent working = Portion of job completed
The man's rate of work is 1/4 of the job per hour, so after 1 hour of work:
1/4 job/hour * 1 hour worked = 1/4 of job completed.
This means 3/4 of the job remains when the son takes over.
The son's rate of work is 1/3 of the job per hour. We also know that he will complete the remaining 3/4 of the job. We are looking for how long it will take him.
1/3 job/hour * Hours worked (h) = 3/4
Put this into an equation and solve for h:
1/3 * h = 3/4
Multiply each side of the equation by 3:
h = 9/4
So, it will take the son 9/4 of an hour...or 2.25 hours...or 2 hours and 15 minutes...to finish mowing the lawn.
