Statistics Unit Review

How many people gave the movie a score lower than or equal to 60?

• 5

• 10

• 15

• 25

Mia recorded the scores she earned for each math homework assignment during the year, then represented that data on a box plot, which is shown.

What is the median score Mia earned on math homework?

• A.  50

• B.  60

• C.  80

• D.  90

How much money did Daphne earn in tips each night, on average?

Answer explanation

Average is the synonym for mean. Add up all the values then divide by the number of values.

Daphne is a full-time college student who works part-time as a server in a restaurant on the weekends.  The amount of money she made as tips for the last eight evenings she worked is shown in the table.

What was the median amount of tips Daphne earned those eight nights?

Rocco recorded how many miles he drove each day for two weeks.  During that time he drove to work most days and took a couple of trips.

Which measure of center best represents the typical amount of daily driving he did during this time, and why?

• The mean is best because the number of data points is small.

• The median is best because the number of data points is small.

• The mean is best because there are outliers in the data set.

• The median is best because there are outliers in the data set.

Answer explanation

Measure of center is referring to the mean and median.

Which of the following are good statistical questions?

• Which hair stylist has worked the longest?

• How much hair, in inches, will Shania trim from her bangs?

• How many haircuts did each stylist in New York City perform last month?

• What time does the Precision Cuts hair salon open Sunday morning?

Why is the question below a good example of a statistical question? How many cell phones did each salesperson in a T-Mobile store sell last month?

• Cell phone sales are recorded in whole numbers, not fractions or decimal numbers.

• Since the salespeople worked last month, the cell phones were actually sold.

• We don’t know how many salespeople worked last month.

• There should be variability in the number of cell phones sold.

After the first six math tests of the school year, Nate had earned the following scores:

84, 91, 95, 86, 80, 92

If he earns an 81 on the next test, what will happen to the mean of his scores?

• It will decrease.

• It will stay the same.

• It will increase.

• It is impossible to determine.

Autumn recorded the price of strawberries, per carton, at each Farmer’s Market for a full year.  She performed the following calculations with the data:

Strawberry cost per carton (average): $7.50

Strawberry cost per carton (median): $7.25

Strawberry cost per carton (mode): $7.30

Strawberry cost per carton (range): $3.25

Which measure shows how the prices of strawberries vary during the year?

• average

• median

• mode

• range

Wendell surveyed the 15 members of the high school soccer team and asked how many years of soccer they had played.  The results are shown in the line plot.

Which of the following statements is true?

• A.  The spread of the data is 5 with a peak at 10.

• B.  The spread of the data is 5 with a peak at 12.

• C.  The spread of the data is 12 with a peak at 10.

• D.  The spread of the data is 12 with a peak at 12.