Transcript To write decimals as fractions.

COURSE 3 LESSON 4-2
Equivalent Forms of Rational Numbers
Write a fraction in lowest terms, with a single digit numerator, that is about
the same as each decimal: 0.52, 0.13, 0.74, 0.88.
1 1 3 7
2 , 8 , 4, 8
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COURSE 3 LESSON 4-2
Equivalent Forms of Rational Numbers
Write 3.225 as a mixed number.
3.225 =
3.225
1
Write as a fraction with the denominator 1.
Since there are 3 digits to the right of the
decimal, multiply the numerator and
denominator by 103 or 1,000.
3,225
= 1,000
3,225 ÷ 25
129
= 1,000 ÷ 25 = 40
9
= 3 40
Simplify using the GCF, 25.
Write as a mixed number.
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COURSE 3 LESSON 4-2
Equivalent Forms of Rational Numbers
Write the repeating decimal 0.23 as a fraction in
simplest form.
Step 1 Let the variable n represent the given decimal.
n = 0.23
Step 2 Since 2 digits repeat, multiply each side by 102, or 100.
100n = 23.23
Step 3 Subtract to eliminate the repeating part, 0.23.
100n = 23.232323 . . .
– n = – 0.232323 . . .
Use the Subtraction Property of Equality.
99n = 23.000000
Simplify.
99n = 23
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COURSE 3 LESSON 4-2
Equivalent Forms of Rational Numbers
(continued)
Step 4 Solve the new equation.
99n
23
=
99
99
23
n = 99
Divide each side by 99.
Simplify.
The repeating decimal 0.23 equals
23
.
99
Check Use a calculator to divide 23 by 99.
23
99
0.23232323
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COURSE 3 LESSON 4-2
Equivalent Forms of Rational Numbers
Write each as a fraction in simplest form.
1. 30
42
5
7
2. – 12
18
3. 2.75
–2
23
3
4. 0.2
5. 0.4
2
9
2
5
4
6. 7.25
7 25
99
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