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31b CN Terminating and Repeating Decimals.notebook
1
Chapter 2
Rational Numbers
Name:
31b CN Terminating and Repeating Decimals.notebook
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Note: When you see a fraction with the denominator of 9, remember that it represents a repeating decimal.
To change a fraction into a decimal, divide the denominator into the numerator.
To change a decimal into a percent, multiply the decimal by 100.
Terminating and Repeating Decimals (31) https://www.youtube.com/watch?v=do_IbHId2Os fraction into decimals
decimals into fractionshttps://www.youtube.com/watch?v=Z8Pz59odpE
31b CN Terminating and Repeating Decimals.notebook
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To change a fraction into a decimal:Divide the numerator by the denominator
ex.
numerator denominator
OR
ex. 15 ÷ 3
Please take out your calculator!
means...
means...
numerator
denominator
denominator numerator
31b CN Terminating and Repeating Decimals.notebook
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Sometimes you will get a:
Repeating decimal: Reminder: use the bar notation to illustrate a repeating decimal
*
Example 1
Example 2
Example 3
Notice the repeating bar is over both the 2 and the 7 because both numbers consistently repeat.
1st method change the mixed number into an improper fraction. Then divide the denominator into the numerator.
=
2nd method place the whole number in your answer box and just work with the fraction. Divide the denominator into the numerator.
= 8.
Method 1 You can recognize that there is a 9 in the denominator. When there is a 9 in the denominator, the decimal equivalent is the numerator expressed as a repeating decimal.
Method 2 divide the denominator into the numerator.
Reminder: the numerator
jumps into the box
31b CN Terminating and Repeating Decimals.notebook
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Sometimes you will get a ...
Terminating decimal:You know it is a terminating decimal because the repeating decimal will be zero. Your division will end because you get zero for a remainder.
Example 4
Example 5
Example 1
Example 2
Example 31st method change the mixed number into an improper fraction. Then divide the denominator into the numerator.
2nd method place the whole number in your answer box and just work with the fraction. Divide the denominator into the numerator.
DON'T FORGET THE NEGATIVE SIGNS IN YOUR ANSWERS.
1st method change the mixed number into an improper fraction. Then divide the denominator into the numerator.
2nd method place the whole number in your answer box and just work with the fraction. Divide the denominator into the numerator.
31b CN Terminating and Repeating Decimals.notebook
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If the denominator of a fraction is a power of ten (10, 100, 1000, etc.) you can:
Use the place value to write the fraction as a decimal.
Example 1
Example 2
Example 3
Example 4
Example 5
Example 6
Example 7
.3
.27
tenths
hundredthstenths
.09tenths hundredths
.103
The 9 must be in the hundredths place value position.
The 7 must be in the hundredths place value position.
tenths
hundredths
thousandths
.057tenths
hundredths
thousandths
The 3 must be in the tenths place value position.
The 7 must be in the thousandths place value position.
You say: three tenths
You say: twenty seven hundredths
You say: nine hundredths
You say: One hundred three thousandths
You say: Fifty seven thousandths
If you can make the denominator a power of 10, here is what you can do...
.35hundredthstenths
The 5 must be in the hundredths place value position.You say: thirty five hundredths
.8tenthsThe 8 must be in the tenths place value position.You say: eight tenths
The 3 must be in the thousandths place value position.
31b CN Terminating and Repeating Decimals.notebook
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Every terminating decimal can be written as a fraction:
To write a decimal as a fraction:Use the place value of the last digit on the right as the denominatorAlways write your answer in simplest form
Example 2: 3.16
Example 1: .4
Example 3: 7.125
Example 4: .055
Think: 4 is in the tenths place value position
Think: 6 is in the hundredths place value position
Think: 5 is in the thousandths place value position
Think: the last 5 on the right is in the thousandths place value position
31b CN Terminating and Repeating Decimals.notebook
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Changing a repeating decimal to a fraction: If one digit repeats, the denominator is 9
If two digits repeat, the denominator is 99
If three digits repeat, the denominator is 999
31b CN Terminating and Repeating Decimals.notebook
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Guided practice workbook page 178
.4 .9 .5
.75 Think: 5 is in the hundredths place value.
Divide the denominator into the numerator.
ex.
31b CN Terminating and Repeating Decimals.notebook
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31b CN Terminating and Repeating Decimals.notebook
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