Another word problem that has me stumped. Can anyone solve it.?

Question

If a pump is to move 18 tons of water to the top of a 22 storey building in one hour, what must be the theoretical horsepower rating of the pump? (Assume that a storey is ten feet. A horsepower is 550 footpounds per second or 33,000 footpounds per minute.)


4.5 ??? I think.

Answer 1

Total work done=18 tons * 2200 lb/ton * 22 storeys * 10 ft/storey
Work done per horsepower per hour=550*3600
Therefore
Number of horse powers required
18*2200*(22*10)/(550*3600)
=44 HP

Answer 2

Why are you stumped. You have the weight, height, and a conversion factor. Seems like a 'plug and chug' to me.