Problem-Solving and Data Analysis practice question

Answer: B. 20%

Percent change = (change / original) × 100 = (50 / 250) × 100 = 20%. The trap (choice C) is dividing by the new value 200 instead of the original 250.

Why the other answers are wrong

A. 15%

15% doesn't come out of these numbers — percent decrease is (change ÷ original) × 100, and here that's (50 ÷ 250) × 100 = 20%.

C. 25%

You divided the change of 50 by the new value 200; percent change always uses the original value, so it's 50 ÷ 250 = 20%.

D. 50%

You reported the raw decrease of 50 as a percent; convert it by dividing by the original 250 first, which gives 20%.

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