Name ÿ Date Period

8th Grade Math TEST Review 2.11

Rate of Change and Slope

1. The graph below shows that Jim is beginning to do small chores around the house to earnmoney. What is the slope of the line?

Chores

18

16

14

12MoneyEarned :o

8

6

4

2

0

|0

i0 15 20 25 30

I% :

Number of Chores

3A5

3B

5D3

w xl

2, The graph below shows the relationship between the number of cookies a bakery sells andthe cost.

What does the slope of the graph represent?

O

4.5¸

4.0

3,5

3.0

2.5

2.0

1.5

1.0

0.5

Y{5¢ _ I__

Iÿrq Lt-

1 2 345678Number of Cookies

F

H

The number of cookies you could buy for $2.00

The cost per cookie

The cookie per cost

The different between buying 2 cookies and 8 cookies

s One point on the line is (-3, 5). What is another point on the line?3. The slope of a line is ÿ.

*USE COORDINATE PLANE TO SOLVE PROBLEM

Y

4, The table shows the relationship between the number of hours, h, John has beenhiking and the total distance, d, he has traveled in kilometers,

John

d 0 5.5 11.0 16.5 22,0 I 527.5

The graph shows the distance Sara hiked over the same time period.ik

30 %/I [- -i.J

2o£

o

10

o0 1 2 3 4 5

hours

What is John's speed?

5,5 ÿ_ra per h0ccrWhat is Sara's speed?

Who is faster?

pÿr hour

qorÿ

m

.ÿ?.oWhat is the constant rate of chÿween

/ V4OTime xÿ

Plane taking of.ÿat the airport./yÿ

H ÿ21

:i_s3

20

12 24

.ÿ i-z,

60

36

k.J

ChCng in <

6, A store sells a 6-pound bag of apples for $11.34.price per pound of apples?

A A 20-pound bag for $36.80 ÿ1,ÿ pe.4r pelÿr'ÿ:;ÿ

B A 12-pound bag for $22.68,ÿ1,ÿq ÿ p#ÿ

C: A 7-pound bag for $13.23 ÿ |'ÿct pt.4r" pOlÿtÿ4

D A 15-pound bag for $28.35 ÿ I .'ÿ91'ÿ;ÿ-'v" ÿ01ÿ1

Which of the1.ÿ--ÿ followingÿl 1. Bqÿis n:t _

I.ÿ

90

the

F!12

--f '2,b 4- 2-0

t wo/ÿ'ÿies in the tÿ

7. Mia works at a shoe store after school to save money for college. She is paid an hourly rateof $8.75 per hour, and she has already saved $700 that her grandparents gave her. Her totalsavings can be represented by the following function. ÿ r. ÿViÿOelqÿ"

8.TSh + 700 = S(h)Z C D C = ConStzÿn+

What is the independent variable in this function?

F The number of dollars given to Mia by her grandparents.

6 The hourly rate Mia is paid.

14 The total amount of money Mia has saved

he number of hours Mia has worked.

x Determine theÿslope of the line that passes through the points E(4, -2) and F(6, 2).

Oÿÿ i ÿy- _ :_ _X2-X, b-q

9. The total cost and the number of watermelons ordered are in a proportional relationship. Therelationship is shown in the graph. Interpret the unit rate and compare it to the slope.

Total Cost ($)

45

40

35

30

25

20

15

10

5

0

Watermelons

/.

/.H"

.jrf .J .............. ,

..... /'ÿ ..... l 2,10 1

,f

0 I 2 4 6

, ÿ 6, 30f" L.ÿ . t-ÿtÿ'onslÿ ipÿ u3 ou.ÿ

X-voÿu4_ is ¢ÿ.

Number of Watermelons

F The unit rate is $2.50 per watermelons, which is also the slope of the line in the graph.

G The unit rate is $10 per watermelons, which is also the slope of the line in the graph.

.ÿhe unit rate is $5 per watermelons, which is also the slope of the line in the graph.

,1 The unit rate is $5 per watermelons and the slope of the line is 10.

10. Red-Box charges $8.94 to rent a DVD for six days. At this rate, which equationcan be used to determine the charge, c, for renting a DVD for eight days?

A c = 1.99(8)

(ÿc 1.49(8)C c = 0.99(8)

D c = 1.29(8)

11. The graph shows the rate in which cars pass a fixed point on a highway. What is the unitrate and what does it represent?

Highway 249

Number of Cars

800

700

600

500

400

300

200

100

0j"

o I

F 300; 300 cars

G 300; 300 miles per hour

H 75; 75 cars

75; 75 car per hour

J¢

4"r'"

Syÿ

.m H r tc

4 6 8

Time(h)10 12

12, Josie rides her bike at a constant rate. The graph of her progress is shown. Whichstatement is true?

Bike Trip

2.5

Miles 1.s

0 '

0 1 2 3

g%

0.5

p,-oloor on4

lO

Time (minutes)rl'Se

A The slope of the line is the same the unit rate of _4 miles per minute. Iÿ1

(ÿhe slope of the line is the same the unit rate of 0.25 miles per minute.#&C The slope of the line is different ÿ the unit rate of 0.50 miles per minute.

1 miles per minute.D The slope of the line is different ÿthe unit rate of so

.4-

H#0,26

DI

::1.3, The table below shows the speed that Diana types. How many words can Diane type in 1

@@0 @188gggÿ

14, What is the slope of this line? Explain how you found the slope.

15. Find the slope of the line that passes through R(8, and S(5, - .