Five observations have mean 6 and the mean of their squares is 40. What is the variance?
A40
B6
C4
D36
Answer & Solution
Correct answer: C. 4
Variance equals the mean of squares minus the square of the mean, so 40 - 36 = 4.
Keep practising Statistics and Probability
Browse all Statistics and Probability questions for AP EAMCET, or explore more Mathematics topics.
Related questions
A series has a coefficient of variation of 12% and a standard deviation of 6. What is its Which measure of dispersion uses only the two extreme values of the data?A set has mean 8 and its mean of squares is 68. What is its standard deviation?What is the variance of the two observations 0 and 10?What is the deviation of an observation x from a fixed value a?The coefficient of variation is also known by which name?The relative mean difference is equal to twice which quantity?The variance of x is 6 and y = 2x + 3. What is the variance of y?