How much water does a 28 foot round by 48 inches pool hold?

Answer 1

Depends on the actual pool (i.e. framed or inflatable ring) but give or take it should be around 15,000 Gallons or 66,000 litres at max capacity

Depends on what you mean by 28ft "round": 28ft circumference or diameter D!

First turn those inches to feet. Easy enough: it's 4.

Then volume = pi/4(Dia^2) * Depth. So if this one of those above-ground bathing-only pools then I'll assume 28ft circumference. If so its diameter = 28/pi = 8.913ft

Then its Volume = ((8.913)^2) (pi/4) (4) = 8.913 X 8.913 X pi = 249.55 cubic feet.

which at 6.23V Imperial gallons per cu ft = 1555 Imperial gallons (rounded).

Not 15,000.

BUT If that 28ft is the Diameter then the volume = 2463 cu ft = 15,345 Imp Galls.