Easy -1.2 This is a straightforward conceptual question requiring students to recognize an obvious outlier (352) and select the median as the appropriate measure. The calculation is trivial (ordering 11 numbers and finding the middle value), and the reasoning is standard textbook material about resistance to outliers. No problem-solving or novel insight required.
1 The salaries, in thousands of dollars, of 11 people, chosen at random in a certain office, were found to be:
$$40 , \quad 42 , \quad 45 , \quad 41 , \quad 352 , \quad 40 , \quad 50 , \quad 48 , \quad 51 , \quad 49 , \quad 47 .$$
Choose and calculate an appropriate measure of central tendency (mean, mode or median) to summarise these salaries. Explain briefly why the other measures are not suitable.
## Question 1:
| Answer/Working | Marks | Guidance |
|---|---|---|
| median | B1 | |
| $\$47000$ | B1 | Must have 47000 |
| data have an outlier, are skew etc | B1 | **3** Accept any equivalent reason |
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1 The salaries, in thousands of dollars, of 11 people, chosen at random in a certain office, were found to be:
$$40 , \quad 42 , \quad 45 , \quad 41 , \quad 352 , \quad 40 , \quad 50 , \quad 48 , \quad 51 , \quad 49 , \quad 47 .$$
Choose and calculate an appropriate measure of central tendency (mean, mode or median) to summarise these salaries. Explain briefly why the other measures are not suitable.
\hfill \mbox{\textit{CAIE S1 2006 Q1 [3]}}