Team Red's five runners took 12, 15, 19, 22 and 30 minutes to finish a trail, and Team Blue's four runners took 14, 17, 25 and 28 minutes. If both teams' times are put in one list, what is the median time?

17 minutesCorrect answerYour answer19 minutesCorrect answerYour answer20 minutesCorrect answerYour answer21 minutesCorrect answerYour answer

Show the answer and explanation

CorrectNot quiteAnswer B

Correct answer: B

Combined list in order: 12, 14, 15, 17, 19, 22, 25, 28, 30.
There are 9 times, so the median is the 5th: 19 minutes.

Worth noting

20 minutes averages the two teams' medians (19 and 21), and 21 minutes is Team Blue's median alone; medians do not combine like that. 17 minutes is the 4th value, one place short of the middle of nine. Merge the lists and find the middle again.

Concept: The median of a combined list must be recomputed
Typical timeTypical: 70 s
Your timeYours: —

The rule this testsWhen values change

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Ten questions from Mean, Median and Mode, at your own pace.

Team Red's five runners took 12, 15, 19, 22 and 30 minutes to finish a trail, and Team Blue's four runners took 14, 17, 25 and 28 minutes. If both teams' times are put in one list, what is the median time?

Explanation