Math Core

This test covers scatter plots and association, lines of best fit and their equations, and two-way tables with relative frequencies.

Question 1

A scatter plot compares the number of hours of daylight and the average daily temperature in a city across a year. The points rise from left to right and lie close to a straight line. Which describes the association?

Question 2

The scatter plot shows minutes of exercise and heart rate (in beats per minute) for seven people right after a workout. Which point is an outlier? Give it as an ordered pair.

x-axis: minutes of exercise. y-axis: heart rate in beats per minute.Open in grapher →

Enter a point like (2, -3)

Question 3

Which description fits this scatter plot?

x-axis: row where the student sits in class. y-axis: score on a 10-point quiz.Open in grapher →

Question 4

In a group of towns, those with more fire trucks also tend to have more house fires. Which conclusion is best?

Question 5

The table shows five data points.

$x$	2	4	6	8	10
$y$	5	9	10	15	17

Which equation is the best line of fit?

Question 6

The scatter plot shows the age of several laptop batteries and how many hours each one lasts on a full charge, along with a line of fit. Use the line to estimate how many hours a $3$ -year-old battery lasts.

x-axis: age of battery in years. y-axis: hours of battery life. The line of fit is drawn.Open in grapher →

Enter a number. Fractions like 3/4 and sqrt(2) are OK.

Question 7

The line of fit for the laptop batteries is $y = -1.5x + 10$ , where $x$ is the age in years and $y$ is the battery life in hours. According to the line, by how many hours does battery life decrease each year?

Enter a number. Fractions like 3/4 and sqrt(2) are OK.

Question 8

In the line of fit $y = -1.5x + 10$ for the laptop batteries, what does the $y$ -intercept $10$ mean?

Question 9

A line of fit passes through $(2, 30)$ and $(8, 12)$ . Write its equation in the form $y = mx + b$ . Enter only the right side.

Enter an expression, e.g. 3x^2 - 2x + 1

Question 10

A school club handed out flyers for a bake sale on several weekends. A line of fit is $y = 0.8x + 5$ , where $x$ is the number of flyers handed out, in tens, and $y$ is the number of visitors. Predict the number of visitors when the club hands out $450$ flyers.

Enter a number. Fractions like 3/4 and sqrt(2) are OK.

Question 11

A line of fit for a set of students is $y = 4x + 50$ , where $x$ is hours of practice and $y$ is the score on a typing test. A student who practiced $5$ hours scored $64$ . How many points below the line's prediction was the student's score?

Enter a number. Fractions like 3/4 and sqrt(2) are OK.

Problems 12 to 15 use this two-way table from a survey of $120$ students. Two entries are missing.

	Has a job	No job	Total
Has a license	27	?	45
No license	18	57	?
Total	45	75	120

Question 12

How many students have a license but no job?

Enter a number. Fractions like 3/4 and sqrt(2) are OK.

Question 13

What percent of the students with a license have a job?

Enter a number. Fractions like 3/4 and sqrt(2) are OK.

Question 14

What percent of the students who have a job do not have a license?

Enter a number. Fractions like 3/4 and sqrt(2) are OK.

Question 15

The "No license" row has $18 + 57 = 75$ students, and $\dfrac{18}{75} = 24\%$ of them have a job. Which conclusion does the table support?