Sarah burns an average of 744 calories in 45 minutes while running. She ran at 10 miles per hour. There are 5,280 feet per a mile. How many calories did Sarah burn per foot? Round to the nearest tenthousandth.
Number of miles ran by Sarah in 1 hour or 60 minutes = 10 miles Then The number of miles ran by Sarah in 45 minutes = (10/60) * 45 miles = (45/6) miles = 15/2 miles = 7.5 miles Now we already get from the question certain important data. From those data we come to know 1 mile = 5280 feet So 7.5 miles = (5280 * 7.5) feet = 39600 feet By running 39600 feet the amount of calories burnt by Sarah = 744 calories So By running 1 foot, the amount of calories burnt by Sarah = (744/39600) calories = 0.019 calories = 0.02 calories So Sarah burns 0.02 calories per feet.
(744 calories/ 45 minutes)* (60 minutes/ 1 hour)* (1 hour/ 10 miles)* (1 mile/ 5,280 ft)= 0.018788 calories/ft. (Note that the units cancel out so you get the answer)
Rounded to the nearest ten thousandth, the final answer is 0.0188 calories/ft~
