Download Math 137 Unit 4 and 5 Review 1) 2)

Math 137 Unit 4 and 5 Review
1)
2)
3)
4)
5) Match the equation to the graph:
6)
The Consumer Report ratings for breakfast cereals have a fairly strong negative linear relationship
with the grams of sugar per serving. The least-squares regression line is:
Predicted rating = 60 – 2.4*sugar
Which of the following is a valid interpretation of the slope?
a) A one-point increase in Consumer Reports ratings corresponds to a predicted decrease of 2.4
points is the grams of sugar in a serving.
b) A one-gram increase in sugar per serving corresponds to a predicted decrease of 2.4 points in
the Consumer Reports rating.
7) Match each Scatter plot to the residual plot:
8)
9)
10)
11)
12)
13) (Review Question) Find the standard deviation for: 11, 14, 18, 16, 10, 15
14) (Review Question)
a) Between 10 and 12
b) 13
c) Between 16 and 18
15) The regression line for predicting a variable y is found to be y  1  3x . Calculate the Standard
Error Se 
SSE
for the following data:
n2
x
3
4
6
7
10
y Prediction
11
10
17
24
31
Error
(Error)2
16) When comparing the linear relation between the price of gas and the number of miles people drive
in a week, the correlation coefficient r = .82. What does the value of r2 tell us about these variables?
17) Find the percent increase or decrease for each of the following:
a)𝑦=2000(1.12)x
d) y=2000(.82)x
b) y=2000(1.03)x
e) 𝑦=2000(.956)x
c)𝑦=2000(1.003)x
f) 𝑦=2000(.12)x
18) The initial number of bacteria in a sample is 150,000 and it grows at a rate of 2% every day.
a) Write an exponential equation for the number of bacteria after t days.
b) Use your equation to predict the number of bacteria after 15 days.
19) A group of scientists observed a population of birds in a remote area and counted the birds in 1998. After
returning every year and counting the birds, they came up with the following formula for the number of
birds: 𝑦=12000×(.84)t.
a) How many birds used to live in the area in 1998?
b) Predict the population in 2010.
20) A researcher has collected data on the price of gasoline from 1992 to 2014 and has found that the
price in dollars after t years can be predicted using the equation: y = − 0.0256t2 +0.3584t +1.90
a) According to this model what was the price of gas in1990?
b) Using this model predict the price of gas 1998?
c) Based on the equation, what year had the most expensive gas?
d) How much did gas cost in that year?
21. The Following ordered pair data describes the grams of fat in a meal and the number of
calories.
a) Use the above information to write a regression line.
b) Write a sentence interpreting the meaning of the slope for the meal.
c) Write a sentence interpreting the meaning of the y-intercept for the meal.
d) Write a sentence interpreting the meaning of r2 for the meal.
e) Write a sentence interpreting the meaning of Se
f) Predict the number of calories in a meal with 37 grams of fat.