<PRE><B>Question 974557</B>
amy can mow a field in 90 minutes. Ty can do the same field in 45 minutes.
How long will it take to mow the football field if they do it together?
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Amy rate 1/90 job/min
Ty rate 1/45 job/min
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Together rate:: 1/x job/min
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Equation:
rate + rate = together rate
1/90 + 1/45 = 1/x
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45x + 90x = 90*45
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135x = 90*45
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3x = 90
x = 30 min (time to do the job together)
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Cheers,
Stan H.
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