What is the average of all two-digit numbers that leave a remainder of 3 when divided by 5?

50.5Correct answerYour answer53Correct answerYour answer54.5Correct answerYour answer55.5Correct answerYour answer

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CorrectNot quiteAnswer D

Correct answer: D

Such numbers are 13, 18, 23, …, 98 (3 and 8 are one-digit, so the list starts at 13).
They are evenly spaced by 5, so average = $\frac{13 + 98}{2} = 55.5$ .

Worth noting

Starting at 3 gives 50.5, stopping at 93 gives 53, and 54.5 is the average of ALL two-digit numbers.

Ten questions from Averages, at your own pace.

Explanation