Illinois State University Mathematics Department

 MAT 312: Probabilistic and Statistical Reasoning for K-8 Teachers Dr. Roger Day (day@ilstu.edu)

 Prep for upcoming Quizzes: Test #2 Prep and Review

Select the letter of the most correct response for each question.

1. Three fundamental characteristics of a two-variable relationship are _?_.

b. strength, shape, and direction
d. shape, location, and direction

2. A linear model relates the number of donuts sold (d) to the profit (P), in dollars, of a donut shoppe. For example, (654, 56.35) represents selling 654 donuts and earning a profit of \$56.35. If the linear relationship P = 0.43d - 224.72 models this relationship, what is the meaning of the slope of the linear equation?

a. When no donuts are sold, there is a profit of \$224.72.
b. When no donuts are sold, there is a loss of \$224.72.
c. Each donut sold generates \$0.43 profit.
d. Each donut costs \$0.43 to produce.

3. In general, which of the following is the least justifiable criterion for positioning a spaghetti line on a scatter plot to represent the relationship between two variables?

a. Position the line to account for the real-world context.
b. Position the line so that about half the data points are below the line and about half the points are above the line.
c. Position the line so that it passes through the origin.
d. Position the line to keep the data points as close to the line as possible.
e. Position the line to account for clusters of points revealed on the scatter plot.

Review Situations

4. Which of the follow data can be best considered as interval data?

a. the place that runners finish in a race (first place, second place, and so on)
b. the number of birthdays parties my daughter attends each year she is in school
c. the temperature inside my oven, recorded every two minutes during the time that I am roasting a Thanksgiving turkey
d. the social security number of the students enrolled in summer courses in the ISU Mathematics Department
e. None of the responses (a) through (d) are best considered as interval data.
f. More than one of the responses (a) through (d) are best considered as interval data.

5. A data set has a highspread of 60 light bulbs and an upper quartile (75th percentile) of 144 light bulbs. If we know the median is 100 light bulbs, what is the upper extreme of the data?

a. 60 light bulbs
b. 120 light bulbs
c. 144 light bulbs
d. 160 light bulbs
e. 204 light bulbs