The water level in a rectangular swimming pool measuring 20 feet by 25 feet is to be lowered by 6 inches. How many gallons of water must be removed? (1 cu ft = 7.5 gallons) Choose the correct choice from the following options
A) 100  B) 250  C) 1875  D) 1200  E) 5625

Rationale: 6 inches = 1 / 2 feet ( there are 12 inches in a foot . ) , so 20 * 25 * 1 / 2 = 250 feet ^ 3 of water must be removed , which equals to 250 * 7.5 = 1875 gallons . answer : c .
Answer: C