We assume the unit rate of interest is dollars per pound. To find that, we divide the number of dollars by the number of pounds. ("Per" essentially means "divided by.")
$2.49/(5 lb) = (2.49/5) $/lb ≈ $0.50/lb
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pounds per dollar is also a unit rate. That one would be
Yes 1,120 gallons per week (7 days) Just divide 800 by 5 and see that the sprinkler system uses 160 gallons a day. Multiply 160 by 7 for the amount used a week and you will find that the answer is 1,120 gallons of water.
