April 15 - Statistics Practice

A data set shows the number of minutes each of 153,477 students takes to complete a reading test. The median completion time is 110 minutes. The interquartile range is 34. Which statement about the completion times is most likely to be true?

• Of these students, 25% complete the test in 110 minutes or less.

• Of these students, 50% complete the test in 110 minutes or less.

• Of these students, 75% complete the test in 127 minutes or less.

• Of these students, 75% complete the test in 144 minutes or less.

A teacher measures the time it takes each student in a class to complete a puzzle. The first quartile value of the teacher’s data is 4 minutes. The third quartile value is 6 minutes. Which statement must be true?

• About 25% of the students completed the puzzle in 4 minutes or less.

• About 50% of the students completed the puzzle in 6 minutes or more.

• Exactly 25% of the students completed the puzzle in exactly 4 minutes.

• Exactly 50% of the students completed the puzzle in 5 minutes or less.

A data set shows a basketball team’s final scores for one season. Some information about the scores in the data set is listed below.

• The minimum value is 42.

• The lower quartile value is 54.

• The median is 60.

• The upper quartile value is 72.

• The maximum value is 90.

Of the team’s final scores for the season, 75% of them are most likely between which two values?

• 42 and 66

• 42 and 72

• 60 and 72

• 72 and 90

The range of the weights, in pounds, of all the goats on a farm is 180. Which statement about the weights of the goats is most likely true?

• The heaviest goat on the farm weighs 180 pounds.

• Exactly 50% of the goats on the farm weigh less than 90 pounds.

• Exactly 50% of the goats on the farm weigh within 180 pounds of each other.

• There is a goat on the farm that weighs 180 pounds more than another goat on the farm.

Kari asked 6 of her friends how many movies they watched during the summer.

Kari determined the following measures about the number of movies watched by the 6 friends.

• mean: 9

• median: 8

• range: 16

The 3 friends who watched the most movies over the summer watched 18, 15, and 12 movies.

How many movies were watched by each of the other 3 friends?

• 1, 4, 4

• 2, 2, 5

• 2, 3, 4

• 2, 4, 4

A data set contains student test scores. • The median test score is 75 points. • The third quartile value is 85 points. • The range of the test scores is 40 points. Which statement about the test scores in the data set is most likely true?

• The lowest test score is 45 points.

• The highest test score is 95 points.

• About 25% of the test scores are less than 55 points.

• About 25% of the test scores are between 75 and 85 points.

Marti has been keeping track of the number of visitors to her new website for the past 9 months. The line graph shows the data Marti recorded. Based on the trend shown in the graph, which will most likely be the number of visitors to Marti’s website for the 12th month?

• 5,000

• 6,000

• 8,000

• 10,000

Brent works at a tire store. He recorded the number of tires sold each day for two weeks in the stem-and-leaf plot. What is the median of the number of tires sold each day?

• 100

• 117

• 121

• 124

The box-and-whisker plot represents the prices of all the cars for sale at a dealership. Based on the box-and-whisker plot, which statement about the prices of the cars is most likely true?

• One-half of the cars are priced at $12,000.

• All of the cars are priced no lower than $10,000.

• One-half of the cars are priced between $14,000 and $25,000.

• One-fourth of the cars are priced between $12,000 and $14,000.