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Name
LESSON
Date
Class
Problem Solving
12-1 Tables and Functions
Use the tables to answer each question.
Table 2
Table 1
miles
kilometers
ounces
2
3.22
1
3
4.83
2
4
5
grams
28.35
3
8.05
Table 3
85.05
4
113.4
gallons
liters
5
10
37.9
15
56.85
20
75.8
1. Write an equation for a function that
gives the values in table 1. Define the
variables you use. Use your equation
to find the missing term in the table.
2. Write an equation for a function that
gives the values in table 2. Define the
variables you use. Use your equation
to find the missing term in the table.
3. Write an equation for a function that
gives the values in table 3. Define the
variables you use. Use your equation
to find the missing term in the table.
4. There are 4 quarts in a gallon. Write
an equation for a function relating
quarts to liters. Then use your
equation to find how many liters of oil
a 50-quart barrel can hold.
Circle the letter of the correct answer.
6. A hummingbird egg only weighs
0.25 grams! How many ounces does
the egg weigh?
F about 7.0875 ounces
G about 0.009 ounces
H about 28 ounces
J about 9 ounces
5. The Rocky Mountains stretch
3,750 miles across North America.
What is this length in kilometers?
A 2,329.2 kilometers
B 1,164.6 kilometers
C 6,037.5 kilometers
D 12,075 kilometers
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Holt Middle School Math Course 1
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LESSON
12-1 Tables and Functions
Practice C
LESSON
12-1 Tables and Functions
A function is a rule that relates two quantities so that each input
value corresponds to exactly one output value. In the table below,
the x-values are the input and the y-values are the output.
Write an equation for a function that gives the values in each
table, and then find the missing terms.
1.
2.
3.
4.
x
2
3
4
5
6
y
4
9
16
25
36
yx2
x 0
1
2
3 4
5
y 4
5
6
7 8
9 10 ?
To write an equation for a table of values, first
compare the x- and y-values to find a pattern.
6 7
Each y-value is 4 more than its corresponding
x-value.
y x (4)
x
32
28
24
20
16
y
8
7
6
5
4
x
1
2
3
4
5
y
7
12
17
22
27
Then use the pattern to write a rule for the table.
yx4
y 5x 2
x
10
8
6
4
2
y
4
3.2
2.4
1.6
0.8
yx4
y74
y 11
So y is 11 when x is 7.
You can use the rule to find a missing value in a table.
To find the value of y in table above when x 7, substitute
7 for x in the equation.
y 0.4x
Write an equation for the function. Tell what each variable you
use represents.
Write an equation for a function that gives the values in each
table. Use the equation to find the value of y for the indicated
value of x.
5. The rate of travel is the quotient of the distance traveled divided
by the time spent traveling.
Possible answer: r d t; r rate; d distance; t time
1. x 1
2
3
6
2. x 18 17 16 15 14 13
y 3
6
9 12 15 ?
y 15 14 13 ? 11 10
6. A taxi driver charges a flat rate of $3.00 and $0.80 per mile
traveled.
4 5
y 3x, y 18
Possible answer: c 3 0.8m; c total charge; m miles
y x 3, y 12
You can also write equations for functions that are described in words.
7. Tony earns $12 per hour for 40 hours a week. For any hour over
40, he earns time and a half, which is the sum of the regular
hourly rate and half that rate. Use your equation to find how
much Tony will earn if he works 45 hours next week.
The length of the pool is 6 times the width of the pool.
length of pool
w width of pool
6w
Possible answer: y 480 18h; y total weekly earnings;
h hours worked over 40 hours; $570
Choose variables for the equation.
Write an equation.
Write an equation for the function. Tell what each variable you
use represents.
8. Explain why the equation y x 2 can have two possible values
of x for every value of y.
3. Todd is 6 inches taller than Scott.
4. Alana is 4 times as old as Tracey.
because the positive and negative of a number squared have the same
t Todd’s height
a Alana’s age
value: 4 22; 4 (2)2
s Scott’s height
t Tracey’s age
ts6
a 4t
10
Copyright © by Holt, Rinehart and Winston.
All rights reserved.
Holt Middle School Math
Course 1
Challenge
LESSON
12-1 Multifunctional Measurements
Holt Middle School Math Course 1
Problem Solving
LESSON
12-1 Tables and Functions
Use the tables to answer each question.
Any function can be written as two different equations—one for
each variable. Write two different equations for the function that
gives the values in each table. Then choose either equation to
answer the question that follows.
Table 1
A stone is a British unit of weight.
Table 2
miles
kilometers
ounces
2
3.22
1
Table 3
grams
gallons
liters
28.35
5
18.95
stones (s)
1
2
3
4
5
3
4.83
2
56.7
10
pounds (p)
14
28
42
56
70
4
6.44
3
85.05
15
56.85
5
8.05
4
20
75.8
14 s
1. p 1. Write an equation for a function that
gives the values in table 1. Define the
variables you use. Use your equation
to find the missing term in the table.
1
2
17 stone
A fathom is a unit sailors use to measure the depth of water.
fathoms (m)
4
6
8
10
12
feet (f )
24
36
48
60
72
6m
113.4
37.9
p ÷ 14
2. s 3. In a competition called Stones of Strength, athletes must
lift five huge rocks onto platforms. The first rock weighs
245 pounds. How many stone does it weigh?
4. f 11
Copyright © by Holt, Rinehart and Winston.
All rights reserved.
Possible answer:
Possible answer:
k 1.61m; k kilometers;
g 28.35z; g grams;
m miles
z ounces
3. Write an equation for a function that
gives the values in table 3. Define the
variables you use. Use your equation
to find the missing term in the table.
f÷6
5. m 2. Write an equation for a function that
gives the values in table 2. Define the
variables you use. Use your equation
to find the missing term in the table.
6. Years ago, sailors on riverboats shouted “mark twain” when the
river’s depth was 2 fathoms—barely deep enough for a boat to
navigate safely. How many feet deep was the water at mark
twain?
12 feet
4. There are 4 quarts in a gallon. Write
an equation for a function relating
quarts to liters. Then use your
equation to find how many liters of oil
a 50-quart barrel can hold.
Possible answer:
Possible answer:
l 3.79g; l liters;
l 0.9475q; l liters;
g gallons
q quarts; 47.375 liters of oil
An acre is a unit for measuring areas of land.
acre (a)
square miles (s)
7. a 1,280
1,920
2,560
3,200
3,840
Circle the letter of the correct answer.
2
3
4
5
6
5. The Rocky Mountains stretch
3,750 miles across North America.
What is this length in kilometers?
A 2,329.2 kilometers
B 1,164.6 kilometers
C 6,037.5 kilometers
D 12,075 kilometers
640 s
8. s a ÷ 640
9. King Ranch in Texas covers about 1,300 square miles—larger
than the entire state of Rhode Island! How many acres of land
does King Ranch cover?
6. A hummingbird egg only weighs
0.25 grams! How many ounces does
the egg weigh?
F about 7.0875 ounces
G about 0.009 ounces
H about 28 ounces
J about 9 ounces
832,000 acres
Copyright © by Holt, Rinehart and Winston.
All rights reserved.
12
Copyright © by Holt, Rinehart and Winston.
All rights reserved.
Holt Middle School Math
Course 1
Copyright © by Holt, Rinehart and Winston.
All rights reserved.
70
13
Holt Middle School Math Course 1
Holt Middle School Math
Course 1