Normally Distributed	Housefly Wing Lengths
length (x.1mm)	frequency
36	1
37	1
38	2
39	2
40	4
41	6
42	7
43	8
44	9
45	10
46	10
47	9
48	8
49	8
50	6
51	5
52	2
53	2
54	1
55	1

Find the mean and standard deviation of the sample of housefly wing lengths.

List the data values that are within 2 standard deviations of the mean. Justify your answer.

What percentage of the data values are within 2 standard deviations of the mean?

Is this consistent with the Empirical Rule? Explain.