4. Converting Decimals to Fractions filled in.notebook
September 26, 2016
Converting Decimals to Fractions
Review:
Convert 0.6 and 0.37 into fractions.
1) First, multiply these decimals by a factor of 10 until you get a whole number: 2) Then, divide these numbers by the same factor of 10 and then reduce: 1
4. Converting Decimals to Fractions filled in.notebook
September 26, 2016
Dealing with Repeating Decimals Recall that the bar indicates a repeating decimal: 1.3 = 1.33333...
Period: the numbers that are repeating infinitely after a decimal.
0.333...= 0.3 the period is 3
0.3272727...=0.327 the period is 27
1.234234...=1.234 the period is 234
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4. Converting Decimals to Fractions filled in.notebook
September 26, 2016
How Do We Convert a Repeating Decimal Into a Fraction?
Let's convert 0.3 into a fraction. We know that 0.3 = 0.33333...
1) Make an equation: let x = 0.3
2) Multiply the equation above by a factor of 10 in order to get the same decimal part on the right hand side of both equations:
10x = 3.3
3) Subtract both equations (the repeating decimal should cancel out):
­
10x = 3.3
x = 0.3
9x = 3
4) Solve for x:
9x = 3
9
9
x = 1
3
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4. Converting Decimals to Fractions filled in.notebook
September 26, 2016
Your Turn: Convert 2.15 into a fraction and show all appropriate steps. 4
4. Converting Decimals to Fractions filled in.notebook
September 26, 2016
Practice!
1) Convert 0.65 into a reduced fraction:
2) Convert 4.2 into a reduced fraction:
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4. Converting Decimals to Fractions filled in.notebook
September 26, 2016
3) Convert 0.145 into a reduced fraction:
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4. Converting Decimals to Fractions filled in.notebook
September 26, 2016
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