CA Foundation · Quantitative Aptitude · Measures of Central Tendency and Dispersion
For the five observations 2, 4, 6, 8 and 10, what is the variance (treating the five values as the whole population)?
The variance is 8. The mean is 6, the squared deviations from it add up to 40, and dividing by the five observations gives 8. Dividing by four would give 10, and 2.83 is the standard deviation.
- A8Correct
- B10
- C40
- D2.83
Explanation
Mean = 30/5 = 6. Squared deviations are 16, 4, 0, 4, 16, which sum to 40. Variance = 40/5 = 8. Dividing by n−1 gives 10, which is the sample variance and not what is asked. 40 is only the sum of squares, and 2.83 is the standard deviation.
Did you get it right without looking?
One question tells you little. A timed set on Measures of Central Tendency and Dispersion shows your real accuracy, how long you take and where you lose marks.
More Measures of Central Tendency and Dispersion questions
- For a distribution of daily sales, the first quartile is ₹24 thousand and the third quartile is ₹36 thousand. What is the coefficient of qua…
- For a moderately positively skewed unimodal distribution, which of the following relations among the three averages holds?
- The ages (in years) of five employees are 2, 4, 5, 9 and 20 (treat as given values). What is the mean deviation about the median?
- The monthly electricity bills (in ₹) of seven households in a Nagpur housing society are 240, 350, 180, 420, 300, 120 and 500. What is the c…
- The shoe sizes of nine customers who visited a Jaipur store in an hour were 6, 7, 8, 7, 9, 7, 8, 6 and 7. What is the modal shoe size?
- In a moderately asymmetrical distribution, the mean is 36 and the median is 34. Using the empirical relationship among mean, median and mode…