# Stats Chapter 2 Online HW

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question
Does the frequency distribution appear to have a normalâ€‹ distribution? Explain. Temperature_ (F) Frequency 35-39 1 40-44 3 45-49 10 50-54 12 55-59 10 60-64 2 65-69 1
answer
Yes, because the frequencies startâ€‹ low, proceed to one or two highâ€‹ frequencies, then decrease to a lowâ€‹ frequency, and the distribution is approximately symmetric.
question
Does the result appear to have a normalâ€‹ distribution? Why or whyâ€‹ not?
answer
Yes, because the frequencies start low comma reach a maximum comma then become low again, and are roughly symmetric about the maximum frequency.
question
________are sample values that lie very far away from the majority of the other sample values.
answer
outliers
question
Class width is found byâ€‹ _______.
answer
subtracting a lower class limit from the next consecutive lower class limit
question
The histogram to the right represents the weightsâ€‹ (in pounds) of members of a certainâ€‹ high-school programming team. How many team members are included in theâ€‹ histogram?
answer
The histogram represents 18 programming team members. (the x-axis shows weight in pounds, but the y-axis is frequency)(you would count the frequency from each bar in the histogram to get total members).
question
The graph to the right compares teaching salaries of women and men at private colleges and universities. What impression does the graphâ€‹ create? Does the graph depict the dataâ€‹ fairly? Ifâ€‹ not, construct a graph that depicts the data fairly. a.What impression does the graphâ€‹ create? b.Does the graph depict the dataâ€‹ fairly?
answer
a. The graph creates the impression that men have salaries that are more than twice the salaries of women. b. â€‹No, because the vertical scale does not start at zero.
question
The graph to the right uses cylinders to represent barrels of oil consumed by two countries. Does the graph distort the data or does it depict the dataâ€‹ fairly? Why or whyâ€‹ not? If the graph distorts theâ€‹ data, construct a graph that depicts the data fairly.
answer
Yes, because the graph incorrectly uses objects of volume to represent the data.
question
The graph to the right shows the braking distances for different cars measured under the same conditions. Describe the ways in which this graph might be deceptive. How much greater is the braking distance of Car A than the braking distance of Carâ€‹ C? Draw the graph in a way that depicts the data more fairly. a. In what way might the graph beâ€‹ deceptive? b. How much greater is the braking distance of Car A than the braking distance of Carâ€‹ C?
answer
a. By starting the horizontal axis atâ€‹ 100, the graph cuts off portions of the bars. b. The braking distance of Car A is about 40â€‹% greater than the braking distance of Car C.
question
Use the pulse ratesâ€‹ (beats perâ€‹ minute) of males in the accompanying data set to construct a frequency distribution. Begin with a lower class limit of 40 and use a class width of 10. Do the pulse rates of males appear to have a normalâ€‹ distribution? b.) Do the pulse rates of males appear to have a normalâ€‹ distribution?
answer
a.) Pulse Rate Frequency 40â€‹-49 2 50â€‹-59 21 60â€‹-69 55 70â€‹-79 41 80â€‹-89 27 90â€‹-99 5 100â€‹-109 2 b.)The pulse rates of males appear to have a normal distribution because the frequencies start low, increase, and then decrease; and are roughly symmetric.
question
Identify the class width and class midpoints. Height (inches) Frequency 59.0-61.9 4 62.0-64.9 25 65.0-67.9 9 68.0-70.9 1 71.0-73.9 0 74.0-76.9 0 77.0-79.9 0 80.0-82.9 0 83.0-85.9 0 86.0-88.9 1
answer
a). What is the classâ€‹ width? 3 b.)What are the classâ€‹ midpoints? 60.45, 63.45â€‹, 66.45â€‹, 69.45 â€‹,72.45 â€‹,75.45â€‹, 78.45â€‹, 81.45â€‹,84.45, 87.45
question
The table below shows the magnitudes of the earthquakes that have occurred in the past 10 years. magnitude Frequency 5.0-5.9 6 6.0-6.9 6 7.0-7.9 13 8.0-8.9 4 9.0-9.9 2 Use the frequency distribution to construct a histogram. Using a loose interpretation of the requirements for a normalâ€‹ distribution, does the histogram appear to depict data that have a normalâ€‹ distribution? Why or whyâ€‹ not?
answer
a.) Does the histogram appear to depict data that have a normalâ€‹ distribution? The histogram appears to roughly approximate a normal distribution. The frequencies generally increase to a maximum and thenâ€‹ decrease, and the histogram is symmetric.