In: Statistics and Probability
Suppose X ~N (3,5) .
Between what x values does about 68% of the data lie? (The range of x values is centered at the mean of the distribution, i.e. 3.)
According to empirical rule, about 68% of the area lies between one standard deviation from the mean.
We are given
Mean = 3
Variance = 5
Standard deviation = SD = sqrt(5) = 2.236068
Mean - 1*SD = 3 - 1*2.236068 = 0.763932
Mean + 1*SD = 3 + 1*2.236068 = 5.236068
Lower X = 0.763932
Upper X = 5.236068