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Converting Fractions to Decimals and Percents (%)
 Can be done 2 ways depending on the fraction you are converting.
1. Using Equivalent Fractions: if the denominator of the fraction can be easily
converted to a power of 10 denominator (10, 100, 1 000, etc.)
-create an equivalent fraction (follow rules) with a denominator of 10, 100,
or 1 000
-using the place value of the digit, convert to decimal
Example:
2/5 = 2
(x2)/5 (x2)
= 4/10
= 0.4 (4 tenths)
3/4 = 3
(x25)/
4 (x25) = 75/100
= 0.75 (75 hundredths)
FRACTION
2/5
EQUIVALENT FRACTION
2 (x2)/ 5(x2)
4/10
=
DECIMAL
4/ 10 =
0.4
= (4 tenths)
3/4
3 (___)/ 4(___)
=___
100
1/2
3/20
4/25
2. Using Division: all other circumstances
-divide the numerator by the denominator
-if there is a repeating decimal, draw a line (bar) over the digit(s) that
repeat (bar notation)
Example:
2/9 = 2 ÷ 9
= 0.22222
= 0.2
FRACTION
DIVISION
DECIMAL
3/4
3 divided by 4
0.75
2/5
2÷5
5/8
5 ÷8
7/20
7 ÷ 20
1/6
1÷6
4/11
4 ÷ 11
Converting to Percents(%)
 Multiply the decimal by 100 by moving the decimal 2 places to the right
 Look to the 3rd digit to see if you round the percent up or keep it the same
Example:
0.222 x 100
0.367 x 100 (the digit 7 tells to round up)
= 22%
= 37%
PRACTICE: CHANGING FRACTIONS TO DECIMALS
Thousands
Hundreds
Tens
Ones
•
Tenth
Hundredth
1) Write in decimal form.
a) 1/10
e) 2/1000
i)
9 6/10
b) 45/100
f) 6/100
j)
4 39/100
c) 131/1000
d) 875/1000
g)
1 11/100
h)
k)
9 5/1000
l)
7 5/1000
23 11/100
Thousandth
2) Use Equivalent fractions to write in decimal form. Show all work.
a) 1/5
b) 17/20
c) 8/25
d)
9 1/4
e)
11 7/20
f)
10 1/2
f)
8 1/9
3) Use long division to write in decimal form. Show all work.
a) 1/3
b) 7/9
c) 5/12
d)
6 3/11
e)
2 5/8
4) Write as a fraction in simplest form.
a) 0.8
=
b) 0.875
=
c) 2.7
d) 4.05
=
=
e) 0.284
=
f) 6.532
=
g) 1.75
=
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