SOLUTION: JACK USUALLY MOWS HIS LAWN IN 6 HOURS. MARYILYN CAN MOW THE SAME YARD IN 5 HOURS. HOW MUCH TIME WOULD IT TAKE THEM TO MOW THE LAWN TOGETHER?

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Question 273690: JACK USUALLY MOWS HIS LAWN IN 6 HOURS. MARYILYN CAN MOW THE SAME YARD IN 5 HOURS. HOW MUCH TIME WOULD IT TAKE THEM TO MOW THE LAWN TOGETHER?
Found 3 solutions by richwmiller, solver91311, stanbon:
Answer by richwmiller(17219)   (Show Source):
You can put this solution on YOUR website!
x/6+x/5=1
5x+6x=30
11x=30
x=30/11= abt 2.72727 hours = abt 2 hrs 44 minutes

Answer by solver91311(24713)   (Show Source):
You can put this solution on YOUR website!

Why do you feel the need to shout? Typing in all caps is the electronic equivalent of shouting and is therefore both annoying and rude.

If A can do a job in x time periods, then A can do of the job in 1 time period. Likewise, if B can do the same job in y time periods, then B can do of the job in 1 time period.

So, working together, they can do

of the job in 1 time period.

Therefore, they can do the whole job in:

time periods.

John

Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website!
JACK USUALLY MOWS HIS LAWN IN 6 HOURS. MARYILYN CAN MOW THE SAME YARD IN 5 HOURS. HOW MUCH TIME WOULD IT TAKE THEM TO MOW THE LAWN TOGETHER?
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Jack's rate: 1/6 job/hr
Marilyn rate: 1/5 job/hr
Together rate: 1/x job/hr
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Equation:
rate + rate = together rate
1/6 + 1/5 = 1/x
Multiply thru by 30x
5x + 6x = 30
11x = 30
x = 30/11 = 2.73 hrs
0.73hr = 0.73(60 minutes) = 43.8 minutes
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Ans: 2 hr and 44 minutes
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Cheers,
Stan H.