SAT Math Multiple Choice Practice Question 477: Answer and Explanation
18. There are k gallons of gasoline available to fill a tank. After d gallons have been pumped, in terms of k and d, what percent of the gasoline has been pumped?
Correct Answer: A
A Variables in the answer choices? Plug in! This is a percent question, so make k = 100 and d = 40. If 40 out of the 100 gallons have been pumped, that equals 40%. So 40% is your target answer. When you plug k = 100 and d = 40 into the answers, only A gives you 40. Plugging In turns a hard question into a much easier question.