Qn 1: The following data are the result of a historical study of the number of flaws found in a porcelain cup produced by a manufacturing firm.

Flaws	Probability
0	0.451
1	0.270
2	0.134
3	0.078
4	0.038

What is the standard deviation value?

Qn 2: Round the intermediate values to 6 decimal places. Round your answer to 4 decimal places. A restaurant manager is interested in taking a more statistical approach to predicting customer load. She begins the process by gathering data. One of the restaurant hosts or hostesses is assigned to count customers every five minutes from 7 P.M. until 8 P.M. every Saturday night for three weeks. The data are shown here. After the data are gathered, the manager computes lambda using the data from all three weeks as one data set as a basis for probability analysis. Assume that these customers randomly arrive and that the arrivals are Poisson distributed. Use the value of lambda computed by the manager and help the manager calculate the probability that during a 10-minute interval fewer thanthreecustomers arrive for any given five-minute interval between 7 P.M. and 8 P.M. on Saturday night.

Number of Arrivals

Week 1	Week 2	Week 3
3	1	5
6	2	3
4	4	5
6	0	3
2	2	5
3	6	4
1	5	7
5	4	3
1	2	4
0	5	8
3	3	1
3	4	3

Round your answers to 4 decimal places when calculating using Table A.3.