Concept Test
A jogger runs away from campus at a steady rate, stops to talk to some
friends, runs away from campus for a little longer, and then returns to
campus. Which graph below could show the jogger’s distance as a function
of time?
Concept Test
Suppose the average rate of change of jobs in Caddo
Parish with respect to time is 10,000 jobs/year for
the period from 1995 to 2005. Which statement is
most accurate?
A) Each year, the number of jobs increased by 10,000.
B) The number of jobs never decreased.
C) Both A) and B)
D) Neither A) nor B)
Concept Test: Which
slope is largest?
80
70
80
60
60
40
50
20
0
100
150
200
40
30
80
75
70
65
60
55
50
45
40
100
20
10
0
150
200
100
150
200
Concept Test
Given the graph on the right of
y = f(x), which of the
below numbers is most
positive?
A: f(2) – f(0)
B: the average rate of change
of f from x = 0 to x = 2
C: the average rate of change
from x = -2 to x = 0
-3
-2
-1
1
2
3
Concept Test
All four linear functions
below are graphed on
the right. Which one is
the red line?
A: y = 4 + x
B: y = 4 – 2x
C: y = 2 – 2x
D: y = 2 – 4x
Interpretation
• Three cars have the following functions that give the total cost
of ownership as a function of the number of miles traveled:
– Car A: y = 15,000 + .14 n
– Car B: y = 28,000 + .20 n
– Car C: y = 22,000 + .09 n
• Which car was most expensive to purchase?
• Which car is the cheapest to operate per mile?
• After 60,000 miles, which car has had the lowest cost of
ownership?
Concept Test
(Multiple answers possible) Which of the below
tables shows a linear function?
x
1
2
3
4
A(x)
-1
-4
-7
-10
x
1
2
3
4
B(x)
1
4
9
16
D: None of the above
x
1
2
4
8
C(x)
3
5
9
17
Concept Test
1. For which functions is y not directly
proportional to x?
2. For which functions is y not a linear function
of x?
x
1
2
3
4
A(x)
-1
-4
-7
-10
x
1
2
3
4
B(x)
-3
-6
-9
-10
x
1
2
3
4
C(x)
-1
4
-9
16
Concept Test
You have been offered three different jobs: job R has a
base salary of $55,000 with annual raises of $2000,
job S has a base salary of $45,000 with annual raises
of $3200, and job T has a base salary of $48,000 with
annual raises of $2000. Assuming you will be
working at this job for many years, how should you
rank the jobs according to the income you will
receive?
A) R, S, T
B) S, R, T
C) R, T, S
D) None of the above
Concept Test
Given two linear equations, how many solutions
can the system have?
A) Exactly one solution or no solution
B) Exactly one solution or infinitely many
solutions
C) Exactly one solution, no solutions, or infinitely
many solutions
D) Any number of solutions
Concept Test
The graph on the right
shows three different
tax systems as a
function of income.
Which represents a
progressive tax (that is,
where richer people pay
a higher percentage of
their income on taxes)?
Concept Test
Which statement below is correct?
A: (-3x2)3 = -3(x2)3 = -3x6
B: (-3x2)3 = -(3x2)3 = -27x6
C: (-3x2)3 = (-3)3(x2)3 = -27x5
D: None of the above
Concept Test
On your logarithmic scale of time, where does
500 years ago fit?
A: closer to the 102 mark than to the 103 mark
B: closer to the 103 mark than to the 102 mark
C: exactly between the 102 and the 103 mark
Concept Test
Which of the following is true?
A: f(x) is exponential and g(x) is
linear
B: f(x) is neither linear or
exponential
C: g(x) is neither linear or
exponential
D: f(x) is linear and g(x) is
exponential
x f(x) g(x)
2 48 43.56
3 53.5 47.92
4 59 52.71
5 64.5 57.98
Concept Test
A population of bacteria is described by y = 200(2.75)t
where t is measured in days. Which statement is
correct?
A: The population is growing at 75% per day.
B: The population is growing at 275% per day.
C: The population is growing at 175% per hour.
D: None of the above.
Concept Test
If all functions below are
graphed, which
graph is the blue
graph?
A)
B)
C)
D)
y = 200(.5)x
y = 200(1.1)x
y = 100(1.5)x
y = 200(.2)x
Concept Test
Which of the below functions has a half life of 8
days? (In all functions, t measures days.)
A: y = 100(1/8)t
B: y = 25(8)t
C: y = 30(1/2)t/8
D: y = 8(1/2)8t
Concept Test
What will the half-life be for the equation y =
50(.5)4t where t is measured in days?
A) .25 days
B) 4 days
C) 50 days
D) None of the above
Concept Test
If you know that log a is about .301, which of
the following statements is true?
A: log(100a) is about 2.301
B: log(a2) is about .090601
C: Both A and B are true
D: Neither A nor B are true
Concept Test
Suppose you know that ln(a) equals .25. What
can you say about ln(ae4)?
A: It equals 4.25.
B: It equals .25 + e4
C: It equals .254.
D: None of the above.