7.5 gallons per cubic ft
water is flowing out at a rate of 8 cubic ft per minute.....and if 1 cubic ft = 7.5 gallons, then 8 cubic ft = (8 * 7.5) = 60 gallons per minute
the pool holds 300 gallons....and is filling up at a rate of 60 gallons per minute.....300/60 = 5 minutes <===
