At a fair, the ages of the visitors to stall P range over 20 years with the youngest aged 15. The ages at stall Q range over 16 years with the youngest aged 22. What is the range of ages of all these visitors together?

23 yearsCorrect answerYour answer36 yearsCorrect answerYour answer38 yearsCorrect answerYour answer53 yearsCorrect answerYour answer

Show the answer and explanation

CorrectNot quiteAnswer A

Correct answer: A

Stall P: 15 to 35 years. Stall Q: 22 to 38 years.
Together the youngest is 15 and the oldest is 38.
Combined range = $38 - 15 = 23$ years.

Worth noting

36 years adds the two ranges, which is only right if the groups do not overlap and touch. The combined range needs the overall extremes. 38 years is the oldest age, not the range.

Concept: Range of combined data
Typical timeTypical: 70 s
Your timeYours: —

The rule this testsRange and spread

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

At a fair, the ages of the visitors to stall P range over 20 years with the youngest aged 15. The ages at stall Q range over 16 years with the youngest aged 22. What is the range of ages of all these visitors together?

Explanation