A random variable X can take the values -1, 0 and 1 with respective probabilities 0.2, 0.5 and 0.3. The expected value of X is:

Related MCQs

• If a variable x takes the values 12 and 24 with equal frequencies, then mean of x is
• If A.M and the coefficient of variation of x are 6 and 50% respectively, then the variable of x is
• If two regression equations x + 5y = 13 and 3x – 2y = 5, then the mean values of x and y are respectively.
• A.M of 40 observations of a variable is 25 and S.D is 4. The sum of squares of all observations is
• The absolute deviations of the values of a variables from the mean are 10, 15, 19, 2, 14. The mean deviation is 15
• If the two regression coefficients are byx = - 0.4 and bxy = - 0.9 then the value of correlation coefficient (r) is
• For a frequency distribution coefficient of skewness = 0.6; mean = 172 and mode = 163. The value of the variance is
• Given a table: Value (greater than) 100 150 200 250 Frequency 50 32 9 0 The number of observations between 150 and 200 is
• The regression equation of y on x is 3x – 5y = - 12 and regression equation of x on y is 2x – y = 7. The value of y when x = 10 is
• If 𝝈𝒙 ൌ 𝟏𝟎, 𝝈𝒚 ൌ 𝟏𝟐, and bxy = - 0.8, then the value of correlation coefficient (r) is