Problema Solution
jack usually mows his yard in 3 hours. Marilyn can mow the same yard in 4 hours. How much time will it take for them to mow the lawn together?
Answer provided by our tutors
Jack DATA:
time = 3 hrs/job ; rate = 1/3 job/hr
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Marilyn DATA:
time = 4 hrs/job ; rate = 1/4 job/hr
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Together DATA:
time = x hrs/job ; rate = 1/x job/hr
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Equation:
rate + rate = together rate
1/3 + 1/4 = 1/x
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4x + 3x = 12
7x = 12
x = 12/7 = 1.71 hrs (time to do the job together)