1. The following table represents the U.S. sources of electrical energy:
Source Number of plant
Coal 50
Hydropower 7
Natural Gas 18
Nuclear 20
Oil 3
Renewables 2
a. Represent the table in a bar chart using frequencies.
b. Construct a pie chart using percentages.
c. Construct a Pareto chart also showing the cumulative percentage.
2. The following data represents the number of days between the receipt of the complaint and the resolution of the complaint:
54 4 35 137 31 27 152 2 123 81 74 27 11 19 126 110 110 29 61 35 94 31 26 5 12 4 165
32 29 28 29 26 25 1 14 13 13 10 5 27 4 52 30 22 36 26 20 23 33 68
a. Construct a frequency distribution and a percentage distribution.
b. Construct a histogram and a percentage polygon.
c. Form a cumulative percentage distribution and plot a cumulative percentage polygon.
d. What would you tell the president of company about how long a costumer should expect to wait for the complaint to be resolved?
3. The following data was collected on the weight of hammers:
234 245 312 457 590 345 820 622 710 189 299 500 478 1000 430 836 439 444
a. Compute the mean, median, and mode.
b. Compute the range, variance, standard deviation, and coefficient of variation.
c. Compute Z-scores. Are there any outliers?
d. Describe the shape of the data set.
4. Given the following data:
58 63 41 42 29 50 62 43 40 34 70 63 55
a. Compute the first quartile, the third quartile, and the interquartile range.
b. List the five-number summary.
c. Construct a boxplot and describe the shape.
5.below is data from a drug cocktail showing the dependence of viscosity on protein concentration.
protein concentration(mg/ml) viscosity(cps)
25 1.2
50 7.4
75 12.1
100 20.0
a.compute the covariance between protein concentration and viscosity?
b.compute the coefficient of correlation between protein concentration and viscosity?
6. The following data represents the number of days absent per year in a population of six employees of a small company
1 3 6 7 9 10
a. Assuming that you sample without replacement, select all possible samples of n=2 and construct the sampling distribution of the mean.Compute the mean of all the sample means and also compute the population mean.Are they equal?
b.Repeat(a)for all possible samples of n=3?
7.A survey found that in a sample of 189 large companies,40 offered stock options to their board members as part of their non-cash compensation packages.For small-to-midsized companies,43 of 180 surveyed indicated that they offer stock options as part of their noncash compensation packages to their board members.
company size
Large Small-Midsized Totals
stock yes 40 43 80
options No 149 137 286
Totals 189 180 369
a.what is the probability that the company offered stock options to their board members?
b.what is the probability that the company is small to midsized and did not offer stock options to their board members?
c.For a large company,what is the probability that it offered stock options to their board members?
d.If the company offered stock options to their board member,what is the probability that it is a large company?
e.Is the size of the company statistically independent of whether stock options are to their board members and why?
8.Given the following data table, where X=the number of retransmissions:
X 0 1 2 3
P(X) 0.35 0.35 0.25 0.05
a.calculate the mean or expected value for the number of retransmissions.
b.calculate the standard deviation for the number of retransmissions.
9.Given a normal distribution with MEAN=50 and STANDARD DEVIATION=4,what is the probability that
a.X greater than 43?
b.X less than 42 ?
c.5% of the values are less than what X value.
d.60% of the values are between what two X values?