Topic 6 Assessment Review Math 7

A valid inference is one that is true about the _____ based on a _______.

• data, whole population

• population, representative sample

• sample, single example

• example, data point

Micah wants to know the most common style of surfboard used at Breakers Point. He surveys surfers at Breakers Point between 8:00 A.M. and 12 P.M. Which of the following statements is true about Micah’s survey? Select all that apply.

• Micah will obtain a random sample by talking to as many surfers as possible.

• The population for the survey is all people who surf at Breakers Point.

• Micah will not get a representative sample.

• Micah's sample will be representative because anyone can surf at Breakers Point.

Brianna surveyed a representative sample of students at her school to collect data about the numbers of Internet-compatible devices they own. Estimate about how many of the 250 students who attend Brianna’s school own exactly two Internet-compatible devices. Use the data in the table.

• About 50 students

• About 100 students

• About 125 students

• About 200 students

Brianna surveyed a representative sample of students at her school to collect data about the numbers of Internet-compatible devices they own. Use the data in the table. Draw a valid inference about students who own three or more devices. Select all that apply.

• Students are more likely to own exactly 2 devices than any other number.

• More students own 3 devices than own more than 3 devices.

• Less than half as many students own 3 or more devices as compared to students who own 1 device.

• About 10 more students own 1 device than own 3 or more devices.

• None of the students own exactly 5 devices.

Brianna surveyed a representative sample of students at her school to collect data about the numbers of Internet-compatible devices they own. Brianna wants to know how many Internet-compatible devices are owned, on average, by people in her town. Can she use her sample data to form a valid inference about the town?

• Brianna can use her sample data to form a valid inference about the town because her school does represent her town’s entire population.

• Brianna cannot use her sample data to form a valid inference about the town because her school does not represent her town’s entire population.

• CityNet

• Able Cable

• Tel-N-Net

• Impossible to determine from the information given.

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

• 14 seventh-graders

• 28 seventh-graders

• 35 seventh-graders

• 42 seventh-graders

Tricia surveys students in her computer class about time spent on computers by students in her school. Is this a representative sample? Explain.

• This is not a representative sample because students in computer class are more likely to use computers than other students.

• This is a representative sample because students in computer class are equally likely to use computers than other students.

• This is not a representative sample because students in computer class are less likely to use computers than other students.

• This is a representative sample because students in computer class are more likely to use computers than other students.

Use the measures of center from the box plots to make an inference about the data. Based on the _____, the plants in Group A grew _____on average, as compared to the plants in Group B.

• means, the same amount

• medians, less

• ranges, the same amount

• third quartiles, more

Use the box plots to make an inference using the variability of the data. The range and IQR are _____ in Group B as compared to Group A, so there is ______ variability in the growth of plants in Group B.

• greater, less

• less, greater

• greater, greater

• less, less