Assignment #7: Descriptive Statistics
1. The incomes for the five employees of Friend’s Furniture are $18,000, $24,000, $24,000, $27,000 and $79,000. Calculate the mean and median salaries. In your opinion, which number gives a better indication of salaries?
2. Julie tells her class that she is going to disregard the lowest of the 10 quiz scores in Math 13 when she determines each student’s final grade. Will this necessarily change a student’s median score? Mean score? Explain.
3. The following are test results for one of my math classes: (Hypothetical!)
65 91 73 56 84 45 88 73 85 96 75 88 73 72 82
The point total possible was 100. From these results find the following: (Round
to 1 decimal place.)
a. Mean:
b. Mode
c. Median
d. Range
e. Standard deviation (attach work for this, or document the calculator steps you used to calculate the answer.)
4. Place these scores on a bell curve and comment on what the curve shows.
A typical bell curve grading distribution would assign a grade of:
Using this distribution, the grades assigned to the scores in this set would be:
5. As Shannon was reading the paper, she was dreaming about a trip to someplace warm! Using the weather chart to the right, answer the following questions.
High Low
Acapulco 88 71
Chihuahua 79 44
Mazatlan 84 47
Mexico City 85 61
Monterey 81 58
Puerto Vallarta 84 58
Veracruz 82 63
a. What is the range and standard deviation for the low temperatures in Mexico?
b. Do the low temperatures for Mexico form a “normal” distribution? Place the temperatures on a normal curve grid to illustrate your answer.
c. When should we pack our bags????
6. A recent Consumer Report article Jenny and Stephanie were reading reported that the mean number of gallons of gas consumed by a “typical American household” in a year is 750 and the standard deviation is 37 gallons. Assuming the data are normally distributed, what percentage of American households consume less than 713 gallons?
