CA Foundation · Quantitative Aptitude · Measures of Central Tendency and Dispersion
The coefficient of variation of a series is 40% and its standard deviation is 16. What is the arithmetic mean of the series?
The mean is 40. Since CV equals standard deviation divided by mean times 100, the mean equals 16 × 100 / 40 = 40. Checking back, 16/40 × 100 gives 40%, matching the given coefficient of variation.
- A6.4
- B25
- C40Correct
- D64
Explanation
CV = (SD/mean) × 100, so mean = SD × 100 / CV = 16 × 100 / 40 = 40. Check: 16/40 × 100 = 40%. The value 6.4 comes from multiplying 16 by 40 and dividing by 100, which is the wrong rearrangement.
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