Standard Deviation of Random Variables

What is the standard deviation of the discrete random variable if the variance is 1.56?

• 1.25

• 1.30

• 1.35

• 1.40

What does this symbol represent?

• Mean
• Median
• Mode 
• Standard Deviation

What does this symbol represent?

• Standard Deviation
• Variance
• Mean Absolute Deviation
• Sigma

What is the variance if the standard deviation is 1?

• 1

• 2

• 3

• 4

If the standard deviation of a data set is 4, what is the variance?

• 2
• 16
• 4

Find the variance of the probability distribution of the random variable X which can take only the values 0, 1, 2, 3, and 4 given that P(0) = 1/10, P(1) = 2/10, P(2) = 3/10, P(3) = 2/10 and P(4) = 2/10.

• 1.54

• 1.56

• 1.58

• 1.60

At Donald's Donuts the number of donut holes in a bag can vary. Help Donald find the mode.
12, 10, 10, 10, 13, 12, 11, 13, 10

• 13
• 12
• 11
• 10

Find the mean of these numbers:
5,11,2,12,4,2

• 4.1
• 6
• 4.5
• 4

When three coins are tossed, the probability distribution for the random variable X representing the number of heads that occur are 0, 1, 2, and 3 given that P(0) = 1/8, P(1) = 3/8, P(2) = 3/8, and P(3) = 1/8. Compute the variance.

• 0.75

• 0.87

• 1.05

• 1.50

If the standard deviation of the probability distribution is 5, what is the variance?

• 15

• 20

• 25

• 30