On hot, sunny, summer days, Jane rents inner tubes by the river that runs through her town. Based on her past experience, she has assigned the following probability distribution to the number of tubes she will rent on a randomly selected day.

x	25	50	75	100	Total
P(x)	.11	.49	.29	.11	1.00

(a) Find the probability expressions. (Round your answers to 2 decimal places.)

(b) Which of the probability expressions in parts (a) to (d) is a value of the CDF?

multiple choice

• Part (a)
• Part (b)
• Part (c)
• Part (d)

On the midnight shift, the number of patients with head trauma in an emergency room has the probability distribution shown below.

x	0	1	2	3	4	5	Total
P(x)	.04	.33	.27	.21	.13	.02	1.00

(a) Calculate the mean and standard deviation. (Round your mean value to 2 decimal places and standard deviation to 3 decimal places.)

(b) Describe the shape of this distribution.

multiple choice

• Skewed to the right
• Skewed to the left
• Symmetric