Question 717777
A room is 15 feet by 12 feet by 9 feet high , it contains an air conditioner that circulates air at rate of (11) cubic meters per hour .

how long does it takes to exchange the air in the room 10 times ,giving your answer to the nearest minute?
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The room's volume = 15*12*9 = 1260 cubic feet.
10 times that = 12600 cu ft
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1 cu meter =~ 35.315 cu ft
11 cm meters/hr = 388.46 cu ft/hr = 6.4744 cu ft/min
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12600/6.4744 = 1946 minutes