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# Hypothesis Tests, Bar Graphs, Variance, Frequencies, Z-score

See attachment. Please show steps/work for problems.

1. During the last 10 years marketing executives believed that the same proportion of adult men and adult women watched TV news programs. The marketing executives would like to perform a statistical test to assure themselves that a greater proportion of women now watch TV news programs than men. What should be used for the Null and alternative hypothesis to perform this test? (PLEASE SHOW WORK)

2. AMR is a computer consulting firm. The number of new clients that they have obtained each month has ranged from 0 to 6. The number of new clients has the probability distribution that is shown below.

Number of new clients Probability
0 0.05
1 0.10
2 0.15
3 0.35
4 0.20
5 0.10
6 0.05

Refer to exhibit above, what is the variance? (PLEASE SHOW WORK).

3. Consider the letters involved in the word STATISTICS.
a). How many "bars" would be involved if you were supposed to construct a bar graph to represent the frequency distribution of letters? (PLEASE SHOW WORK)

b). What is the relative frequency of letter I? (PLEASE SHOW WORK)

4. For a standard normal distribution, the probability of obtaining a z value between -2.4 to -2.0 is?