Question

a 100 meter dash was held with 20 contestants. the best time was 10.7 seconds, and the worst time was 15.3 seconds. only the fastest 10 contestants advance to the final race. which measure of central tendency should be used to calculate the cutoff time for the final race?
a. range
b. mean
c. median

Explanation:

• Option A: Range is a measure of dispersion (difference between max and min), not central tendency, so A is incorrect.
• Option B: Mean is the average, but with 20 contestants and needing the top 10 (middle - ranked when sorted), mean isn't suitable as it's affected by outliers.
• Option C: Median is the middle value of a sorted dataset. For 20 contestants, when times are sorted, the median will be the average of the 10th and 11th values. The 10th value (when sorted from fastest to slowest) will be the cutoff for the top 10, so median is the right measure of central tendency here.

Answer:

C. median