Swimming Pool Calculator

Pre-Algebra · Axiom Academy

LESSON Swimming Pool Calculator How much water does a pool hold? It comes down to one idea: area of the base, times depth — then convert to gallons. 1. Volume Is the Base, Stacked Up Picture the pool's floor — a flat rectangle. Its area is just length times width. Now imagine filling the pool one thin layer of water at a time: every layer is a copy of that base, and you stack them until you reach the depth. Volume is the base area carried all the way up. Base area first: length × width Cubic feet measure space ; gallons measure water . They're linked by one fixed fact: a single cubic foot of water is about 7.48 gallons . So to find gallons, you don't recompute anything — you just scale the volume you already have by 7.48. Each cubic foot becomes more than seven gallons, so the gallon count is always the bigger number. If your gallons come out smaller than your cubic feet, you've divided by mistake. Now that the pool is measured in gallons, fill time is a sharing problem: total gallons split up over how many you add each minute. A typical garden hose runs about 5 gallons per minute , so the water climbs steadily while the minutes tick by. Gallons on top, gallons-per-minute on the bottom 4. Pools That Aren't Rectangles Plenty of pools are L-shaped, T-shaped, or have a tacked-on spa. You don't need a new formula — you break the shape into rectangular boxes , find each box's volume the usual way, and add them. This trick is called a composite figure .

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