Bluebook SAT Test Two-Variable Data: Models and Scatterplots 9

Question 1

A scatterplot shows data modeled by y = 3x² + 2. What is the predicted value of y when x = 4?

Accepted Answer

50

Answer

48

Answer

14

Answer

54

Question 2

In a linear model y = mx + b, the slope m is negative. Which of the following is true as x increases by 1?

Accepted Answer

y decreases by |m|

Answer

y increases by m

Answer

y stays constant

Answer

y decreases by b

Question 3

A scatterplot shows points (1, 4), (2, 7), (3, 10), (4, 13). Which equation fits this data exactly?

Accepted Answer

y = 3x + 1

Answer

y = 4x

Answer

y = 2x + 2

Answer

y = 3x + 4

Question 4

The line of best fit for data on weekly exercise hours (x) and resting heart rate (y, bpm) is y = −2.5x + 80. What does the −2.5 represent?

Accepted Answer

For each additional hour of exercise per week, the resting heart rate decreases by 2.5 bpm on average.

Answer

The resting heart rate when exercise = 0 is −2.5 bpm.

Answer

The maximum decrease in heart rate is 2.5 bpm.

Answer

Exercise decreases heart rate by 2.5% per hour.

Question 5

A best-fit line passes through (0, 5) and (10, 25). What is the equation of this line?

Accepted Answer

y = 2x + 5

Answer

y = 2.5x + 5

Answer

y = 2x − 5

Answer

y = 5x + 2

Question 6

A scatterplot of x and y has r = −0.88. Which of the following best describes the relationship?

Accepted Answer

Strong negative linear relationship

Answer

Weak negative linear relationship

Answer

Strong positive linear relationship

Answer

No linear relationship

Question 7

Data shows a pattern y ≈ 4 · 2^x. Which model best describes this data?

Accepted Answer

Exponential

Answer

Linear

Answer

Quadratic

Answer

Constant