Slope
Two-way tables
Scatter Plots
Scatter Plots Cont.
Random
100
What is the equation of the line that goes through the points (4, 6) (2, 12)?
HINT: Find the slope first m = (y2 - y1) / (x2 - x1)
Then choose one of the points in the equation y=mx+b to solve for b
y = -3x + 18
100
The graph shows the relationship between two variables. Which scenario is BEST represented by the graph?
a. The value of a car decreased at a constant rate, remained constant for a while, and then began to increase.
b. The number of animals in the local zoo increased at a constant rate over the first ten years after the zoo opened.
c. The average rainfall in a town was constant for the first 4 months of the year. Over the next 6 months it increased and then gradually decreased.
d. The number of customers in a diner increased at a constant rate during the morning hours, remained the same during lunch, and decreased during the afternoon hours.
D. The number of customers in a diner increased at a constant rate during the morning hours, remained the same during lunch, and decreased during the afternoon hours.
100
What correlation would you expect on a scatter plot that is graphing time spend studying vs. time spent playing video games?
Negative association or Negative correlation
100
Which scatter plot has a stronger correlation?
The second scatter plot
100
Sammy rents a truck from U-Haul. They charge $40 for the rental plus $0.25 for every mile driven. Write this linear equation in slope-intercept form.
y = 0.25x + 40
200
Kasey opens a savings account. She uses the equation: y =$25x + 500 to help her keep track of her savings, where y is the amount of money in her account and x is the number of weeks. Which statement is true?
a. Kasey invests $500 per week.
b. Kasey started her savings account with $25.
c. Kasey plans on investing $100 every 4 weeks.
d. Kasey will take $25 per week from her account.
C. Kasey plans on investing $100 every 4 weeks.
200
Look at the graph. When did Denise stop walking?
a. Between 0 and 1 seconds
b. Between 1 and 3 seconds
c. Between 3 and 6 seconds
d. Between 6 and 10 seconds
B. between 1 and 3 seconds
200
The graph represents the measurements of members of the 9th grade baseball team. Which statement best summarizes the relationship?
a. The more weight a student gains, the shorter they are.
b. The more someone weighs, the taller they must be.
c. As players get taller, they tend to weigh more.
d. There is no relationship between height & weight.
C. As players get taller, they tend to weigh more.
200
The line of fit for this scatter plot has a y-intercept of about 250. True or False?
True
200
In a class project, Breanne determines that her plant growth can be described by the equation where y=0.25x + 2 where x = days and y = height of the plant in centimeters.
In the equation, what does 0.25 represent? Be specific!
The growth of the plant each day, or it grows 0.25 inches each day, etc.
(Answers may vary, saying "the slope" is not enough)
300
Write the linear equation for the graph below
y = -1/2x + 6
300
A marketing firm surveyed 200 people to determine their preference for coffee or tea. This two-way table shows the results of the survey. Of all the people in the survey, how many women in the survey preferred coffee?
69 women preferred coffee
300
What correlation would you expect on a scatter plot that is graphing distance of road trip vs. amount of money spent on snacks at gas stations.
Positive association or Positive correlation
300
True or False: This is a good line of best fit.
True
300
Fernando cleans pools for the summer for $25 an hour plus a supply fee of $15.
Part A) Write an equation models the cost for having Fernando clean a pool for hours.
Part B) Then find out how much he will make for a 3-hour cleaning cost.
A) y = 25x + 15
B) $90
400
What is the equation of the linear relationship shown in the table?
y = 3x + 1
400
This two-way table shows the results of a survey about gender and time spent exercising. In the table, is there an association between the number of hours spent exercising weekly and gender?
Explain your answer in a full sentence.
Yes, there is a positive association because there were both more males and females spent more than 10 hours exercising per week than those who spent less than 5 hours exercising per week.
(Answers will vary)
400
What is also called a trend line and is drawn on a scatter plot to make predictions?
Line of fit, or Line of best fit
400
What is the expected sales amount if the temperature is 20 degrees Celsius?
About $450
(Anything close to $450 will also be accepted)
400
A survey was taken of students athletes who play football and lacrosse at Generic High School. 65 boys were on the football team along with 5 girls. 24 girls are on the lacrosse team and a total of 125 students were surveyed.
How many boys are on the lacrosse team?
26 boys on the lacrosse team
500
This is the slope of a vertical line.
What is undefined?
500
A math teacher recorded the color of students’ eyes and hair. This two-way frequency table shows the results of the survey. What percentage of the students have brown hair and brown eyes?
25%
500
When you are writing an equation for the line of best fit, how do you determine the y-intercept?
Write your answer in a full sentence.
Look at where the line of fit crosses the y-axis.
(Answers may vary)
500
What is the time I should spend studying if I would like to get a 90% on the final. 
8 hours, or 8.5 hours
(Anything between 8-8.5 will also be accepted)
500
A marketing firm surveyed 200 people to determine their preference for coffee or tea. This two-way table shows the results of the survey. Of all the people in the survey, what percent were women who preferred coffee?
34.5% or 35%
because 69/200 = 0.345 x 100 = 34.5