Samples Surveys and Inferences

The dot plot shows a random sample of the number of fish caught and released by 30 participants during a two-day fishing tournament. Select the inference that can be made based on the data collected.

• On average, most participants caught and released 5 or more fish.

• More participants caught 6 fish than any other number.

• The same participants who caught and released 1 fish the first day caught and released 1 fish on the second day.

• On average, participants caught and released more fish on Day 2.

What inference is probably true based on the mean and median of the scores below? Blue Team Averages per quarter: 91%, 88%, 87%, 90% Green Team Averages per quarter: 88%, 85%, 82%, 89%

• The Blue team had slightly higher grades, on average.

• The Green team had slightly higher grades, on average.

• The Blue and Green teams had the exact same scores, on average.

• The Blue team’s scores were twice as great as the Green team’s scores.

Brazil asks 7 classmates how many erasers and pens they carry in their bags. The mean number of erasers is 10. The mean number of pens is 4. What inference could Brazil make using this data?

• Most of Brazil's classmates carry more pens than erasers in their bags.

• All of Brazil's classmates carry more erasers than pens in their bags.

• Most of Brazil's classmates carry more erasers than pens in their bags.

• Most of Brazil's classmates carry similar amounts of erasers and pens in their bags.

If you compare the medians of each data set, who spends more time online?

• Seventh graders

• Eight graders

• Both grades spend an equal amount of time online.

• Impossible to determine form the data sets.

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 are likely to vote for the dog park?

• 25

• 125

• 2,625

• 8,750

A random sample of 50 was taken from a shipment of 12,000 light bulbs. There were 2 broken bulbs in the sample. How many broken bulbs would you expect in the entire shipment?

• 240

• 480

• 2,400

• 4,800

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.

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

• Finn's Data Set

• Jonah's Data Set

A family is looking for a new home. The family is comparing homes in two towns. The median home price of Town 1 is ​$450,000. In Town 2, the median home price is ​$384,393. Based on the median home prices of each​ town, what inference can be​ made?

• The homes in Town 2 are more expensive.

• The homes in Town 1 and Town 2 are similarly priced.

• The homes in Town 1 are more expensive.

Lucy collects data from a random sample of seventh-graders. Out of 40 respondents, 7 attend after-school programs. Of the 200 seventh-graders attending Lucy’s school, how many would be expected to attend afterschool programs?

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