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NAME _____________________________________________ DATE __________________ PERIOD _________
Lesson 1 Reteach
Rational Numbers
To express a fraction as a decimal, divide the numerator by the denominator.
Example 1
3
Write −
as a decimal.
4
3
−
means 3 ÷ 4.
4
3
The fraction −
can be written as 0.75, since 3 ÷ 4 = 0.75.
4
Example 2
Write -0.16 as a fraction in simplest form.
16
-0.16 = - −−−
100
4
= - −−
25
0.16 is 16 hundredths.
Simplify.
4
The decimal -0.16 can be written as - −−
.
25
Copyright © The McGraw-Hill Companies, Inc. Permission is granted to reproduce for classroom use.
Example 3
−
Write 8.2 as a mixed number in simplest form.
−
Assign a variable to the value 8.2. Let N = 8.222… . Then perform the operations on N to
determine its value.
−
N = 8.2 or 8.222….
10(N) = 10(8.222)
10N = 82.222…
-N = 8.222…
9N = 74
9N
74
−−
= −−
9
9
2
N = 8−
9
Multiply each side by 10 because 1 digit repeats.
Multiplying by 10 moves the decimal point 1 place to the right.
Subtract N
= 8.222… to eliminate the repeating part.
10N - 1N = 9N
Divide each side by 9.
Simplify.
−
2
The decimal 8.2 can be written as 8 −
.
9
Exercises
Write each fraction or mixed number as a decimal.
2
1. −
0.4
5
−
2
5. - −
-0.6
3
3
2. −−
7
3. −
0.3
10
0.875
8
−
2
6. -1 −
-1.2
9
−
2 6.6
7. 6 −
3
16
4. 2 −−
25
2.64
−−
3
8. -4 −−
-4.27
11
Write each decimal as a fraction or mixed number in simplest form.
− 1
−
3
7
4
9. 0.8 −−
10. -0.15 - −−
11. 0.1 −
12. 1.7 1 −
5
Course 3 • Chapter 1 Real Numbers
20
9
9
1
NAME _____________________________________________ DATE __________________ PERIOD _________
Lesson 1 Skills Practice
Rational Numbers
Write each fraction or mixed number as a decimal.
1
1. −−
10 0.1
1
2. −
8 0.125
3
3. - −
-0.75
4
4. - −
21
5. −−
-0.42
9
6. -3 −−
9 4.36
7. 4 −−
7
8. −
4
-0.8
5
50
-3.45
20
25
−
0.7
9
−
1
-1.16
9. -1 −
6
5 0.−−
15
11. −−
15
−−
7.27
3
12. 7 −−
33
−
-2.26
4
10. -2 −−
11
7
14. 0.7 −−
9
13. 0.9 −−
10
10
23
25
21
25
15. 0.84 −−
16. -0.92 - −−
3
25
17. -1.12 -1 −−
7
-2 −−
19. -2.35
20
18. -5.05
20. 8.85
1
-5 −−
20
17
8 −−
20
−
1
21. -0.1 - −
−
8
22. 4.8 4 −
7
−
23. 6.7 6 −
−
4
24. -8.4 -8 −
9
9
2
9
9
Course 3 • Chapter 1 Real Numbers
Copyright © The McGraw-Hill Companies, Inc. Permission is granted to reproduce for classroom use.
Write each decimal as a fraction or mixed number in simplest form.