CMA Foundation · Fundamentals of Business Mathematics and Statistics · Measures of Central Tendency and Dispersion
A cyclist's mean of five observations is 30. When a sixth observation is added the mean becomes 32. What is the value of the sixth observation?
The sixth observation is 42. The first five values total 150 since the mean is 30, and with six values at a mean of 32 the total becomes 192. The difference, 42, is the added observation.
- A32
- B40
- C42Correct
- D38
Explanation
Original total = 5 × 30 = 150. New total = 6 × 32 = 192. Sixth observation = 192 − 150 = 42. Choosing 32 wrongly assumes the new item equals the new mean.
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