Friendly Travel Agency provided the following table of information. The table gives the number of customers per day who use a credit card and the probabilities of each.

Number of People Placed on Hold, x	P(x)P(x)
0	0.48
1	0.1
2	0.15
3	0.09
4	0.18

Fill in the missing probability.

Part 2 of 2

a. Find the mean of the probability distribution.

b. Find the standard deviation of the probability distribution.

c. What is the probability that at least two people will be put on hold?

I got part one correct, however, I keep getting part two (a, b, and c) wrong. Please can someone demonstrate how to solve this equation. I am hoping to be able to understand this before the test.

the next questions are ones that were marked wrong on my pre-quiz assignment. Please show me the correct way to do these problems.

- The time it takes me to wash the dishes is uniformly distributed between 8 minutes and 16 minutes. What is the probability that washing dishes tonight will take me between 13 and 14 minutes? Give your answer accurate to two decimal places.

- The probability density of a random variable X is given in the figure below.

0 1 2

X

From this density, the probability that X is at least 1.3 is: