Bivariate Data Unit Test

A data set is given: (9, 10), (1, 7), (5, 0), (6, 1), (10, 2), (1, 2), (9, 1), (4, 3)

What type of association exists between the data points?

• positive association

• negative association

• positive then negative association

• no association

Cassie decided to do an informal survey while riding the bus to school. She asked each girl her age and what size shoe she currently wears. Her results are shown in the scatterplot below.



According to the data, which of the following BEST describes the relationship between age and shoe size?

• positive linear association

• negative linear association

• positive non-linear association

• negative non-linear association

The scatterplot below shows the number of bats in an area for the past 10 years.

Which equation best fits the data?

• y = –300x + 8,500

• y = –200x + 9,000

• y = 200x + 9,000

• y = 300x + 8,500

The graph below shows the amount of time students spent on homework and the amount of time spent working at a job each week.

Which equation best fits the data?

The scatterplot below shows the value of a boat over several years.

Which equation best fits the data?

• y = –8,000x + 58,000

• y = –5,000x + 60,000

• y= 5,000x + 60,000

• y = 8,000x + 58,000

The scatterplot below shows the population of seals in an area since 2000.

Based on a linear model, what does the slope represent?

• The number of seals in the area in 2000 was 2,500.

• The number of seals in the area in 2001 was 4,000.

• The seal population increased by about 140 seals a year.

• The seal population increased by about 200 seals a year.

What type of correlation most likely occurs between a person’s age and the number of his or her siblings?

• positive correlation

• negative correlation

• negative then positive correlation

• no correlation

The scatterplot below shows hours studied as related to exam grades in Mr. White’s English class.

Using a linear model, what would be the best estimate of a student’s score if the student did not study for the test?

• 70

• 50

• 30

• 0

A teacher surveyed her class to determine the number of hours students studied for a test and whether they passed the test. Her results are shown below.

                          0-1 Hr            2-3 Hrs              4 or more hrs 

Passed                   3                       9                          12
Didn't  passed      4                       1                           0
 
Approximately what percent of students that passed the test studied 2 to 3 hours?

• 31%

• 34%

• 38 %

• 45%

The relationship between grades on a test and the amount of time studied is graphed in the scatterplot below.

The line of best fit for this data set is y = 0.86x + 36.59. What is the meaning of the slope?

• If students do not study, they can expect a grade of 36.

• For every 10 minutes students study, they can expect their grade to improve by 8.6 points.

• For every 10 points more in the test score, students must study an additional 8.6 minutes.

• If students study for 1 hour, they can expect a grade of 86