Lesson 9.2: Converting “Easy” Fractions to Decimals and Percents

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Transcript Lesson 9.2: Converting “Easy” Fractions to Decimals and Percents

Lesson 9.2:
Converting “Easy” Fractions
to Decimals and Percents
2
5
1
2
1
4
3
25
Mental Math
For each fraction, write the equivalent decimal and
percent on your white board.
36
Example:
You would write: ____ and ____
100
87
100
19
100
3
10
1
2
7
20
Math Message
Complete Problem 1 on Journal page 252.
Using “Easy” Fractions
• Remember that a percent literally means, “per”
“cent”, or per one hundred.
• It is easy to rename a fraction as a percent
when the denominator is 100 because the
fraction is per 100.
For example,
87 has another name, 87%.
100
What are “easy” fractions?
Any fraction, whose
denominator is a
factor of 100.
1 1 1 1
, , ,
2 4 5 10
Using equivalent fractions to change
“easy” fractions into percents.
Ask yourself, what can I multiply the denominator
by to equal 100.
For example, 5 * ___ = 100
Then remember that whatever you do to denomi,
you must do to nume.
2
5
* ____
* ____
Solve Problems 2-4 on page 252 with a partner.
Solve problems on MJ page 253 alone.
“Easy” Fractions MJ pages 342
and 343.
Which are the “easy” fractions?
How do you know?
Let’s try a problem from
tonight’s homework…