dimensional analysis

Question

At many fine museums and college campus they have a “reflecting pool” which is a long shallow pool where the water reflects some pretty scene. At a local museum there is a reflecting pool 15 yards by 18 feet by 4.5 inches deep. What is the volume of the pool in cubic feet? If 7.48 gallons = 1 cubic foot, then how much water is needed to fill the pool in gallons? If a gallon of water weighs 8.35 pounds, how much does the water in the reflecting pool weigh?

Answer 1

So the pool is in the shape of a rectangular prism. To find the volume of this shape, we need Volume = Length*Width*Height. To find the volume in cubic feet, we'll convert all of the values to feet.

1 yard = 3 feet

So,

(15 yard)*(3 feet/yard) = 45 feet

1 inch = 1/12 ft, or 12 inches = 1 ft

(4.5 inches)*(1 ft/12 inches) = 0.375 (or 3/8) ft

Now that we have everything in feet, we can use the formula for volume:

V = (45 ft)*(0.375 ft)*(18 ft) = 303.75 ft³

Converting to gallons

7.48 gal = 1 ft³

(303.75 ft³)*(7.48 gal/1 ft³) = 2272.05 gal

Finding the weight

1 gal water = 8.35 lbs

(2272.05 gal)*(8.35 lbs/1 gal) = 18971.6175 lbs of water