Generalizations Based on Random Samples

Keyli gathers the heights of a random sample of six graders and seventh graders and displays the data in box plots. What can she say about the data sets?

• The 6th grade sample has greater variability.

• The 7th grade sample has greater variability.

• The 6th grade sample has the greater median.

• The ranges are equal for both samples.

Mr. Jackson had students grow the same type of plant in two different rooms to test the growing conditions. The results are shown in the box plant. Choose ALL accurate statements below.

• Room 7G has the tallest plant.

• 75% of 7D plants are 8 in. or taller.

• 7G has a greater median height.

• Room 7D has the shortest and tallest plants.

Kerron gathers the heights of a random sample of 6th graders and 7th graders and displays the data in box plots. Which statement below is true?

• The median of the 7th grade sample is greater than the 6th grade sample.

• The 7th grade sample has greater variability.

• The ranges of both data samples are equivalent.

• The median of the 6th grade sample is greater than the 7th grade sample.

Mykel surveyed 15 7th graders and 15 8th graders at his school to see how many hours they spend per day listening to music. He made two box plots to compare the data sets. What inference can he draw from the data sets?

• The range is greater for the 8th graders, so there is greater variability for the 8th graders than the 7th graders.

• The person who listens to music the least is a 7th grader.

• The median is greater for the 7th graders, so they generally spend more time listening to music than 8th graders.

• No inferences can be made from the box plots.

A random survey of seventh- and eighth-grade students was conducted to find out how many hours are spent doing homework each night. Of the two sets of data, which has the greater median?

• Seventh graders

• Eighth graders

• They have the same median.

• Impossible to determine from the box plot.

Which data set shows students who tend to spend more time on homework per week?

• Finn's Data Set

• Jonah's Data Set

The box plots describe the heights of flowers selected randomly from two gardens. What is the median of the flowers in Garden Y, in inches? ________ inches

A town has 35,000 registered voters. A random sample of 500 voters finds that 125 are in favor of a new dog park. How many voters are likely to vote for the dog park?

• 8,750

• 2,625

• 125

• 2,500

A manager of a local store samples the receipts of every fifth person who goes through the line.  Out of 50 people, 4 had an item that was priced incorrectly.  If 600 people go through his store each day, how many people would you expect to have an incorrect price?

• 30

• 25

• 48

• 50