Question

Barabas received a mark of 50% on a recent test. Barabas answered 13 of the first 20 questions correctly. Barabas also answered 25% of the remaining questions on the test correctly. If each question on the test was worth one mark, how many questions in total were on the test?

Answer 1

32

Explanation:

You want the total number of questions on the test if the final score was 50%, and there were 13 correct out of the first 20, and 25% correct among the remainder.

Setup

Let q represent the number of questions on the test. Then (q-20) is the number of remaining questions, and the number correct is ...

13 +0.25(q -20) = 0.5(q)

Solution

8 +0.25q = 0.5q . . . . . . . simplify

8 = 0.25q . . . . . . . . . . . . subtract 0.25q

32 = q . . . . . . . . . . . . . . multiply by 4

There were 32 questions in total on the test.