Download 2-1 Rational Numbers

Warm Up
Divide.
1. 36  3
2. 144  6
3. 68  17
4. 345  115
5. 1024  64
Warm Up
Divide.
1. 36  3
3. 68  17
5. 1024  64
12
4
16
2. 144  6
4. 345  115
24
3
2-1 Rational Numbers
Objectives
• Math
Write rational numbers in
equivalent forms.
Standard/s:
Number Sense 1.5, 1.3
• Language
Write, pronounce, and
give an example of the key
vocabulary.
Vocabulary
• rational number
12
-3
15
1
2
• terminating decimal
1.25
2.375
• repeating decimal
-0.16
0.81
• can be written as a
fraction, the
denominator = 0
• When dividing, the
decimal remainder = 0
• When dividing, the
decimal repeats
Helpful Hints
-1 = 1 = 1
6 -6
6
Write a fraction as a decimal
Example A
1st)
2nd)
5
4
1.25
4 5.00
-4
10
-8
20
-20
0
Steps
1. Write the problem
2. Divide the numerator
(top) by the
denominator (bottom)
Writing Terminating Decimals as Fractions
Example A
1st)
-5.25
2nd)
25
-5 100
3rd)
25 ÷ 25 = 1
-5 100 ÷ 25 = 4
1
-5
4
Steps
1. Write the problem
2. Convert the decimal to
a fraction based on its
place value
3. Write in simplest form
Writing Repeating Decimals as Fractions
Example A
1st)
2nd)
3rd)
4th)
0.27
27.0
27
99
27 ÷ 9 = 3
99 ÷ 9 = 11
x= 3
11
Steps
1. Write the problem
2. Move the decimal to the
right when the digits
repeat.
3. Draw a fraction bar and
write a nine under each
digit.
4. Write in simplest form
Guided Practice
Guided
p. 68; 6, 15, 23
_______________________________________
If you finish early, use a loose sheet of paper for
Independent Practice
27-68 all
Homework
• p. 68; 27-52, 55, 61, 65, SSR odd
or
• GO.hrw.com MT8CA 2-1 and
SSR odd
or click
http://my.hrw.com/math06_07/nsmedia/homework_help/msm2_ca/msm2_ca_ch02_01.html
Lesson Quiz
Write each decimal as a fraction in
simplest form.
1. 0.27
2. –0.625
13
3. Write
as a decimal.
6
4. Tommy had 13 hits in 40 at bats for his
baseball team. What is his batting
average? (Batting average is the
number of hits divided by the number
of at bats, expressed as a decimal.)
Lesson Quiz
Write each decimal as a fraction in
simplest form.
5
27
–
1. 0.27
2. –0.625
8
100
13
3. Write
as a decimal. 2.16
6
4. Tommy had 13 hits in 40 at bats for his
baseball team. What is his batting
average? (Batting average is the
number of hits divided by the number
0.325
of at bats, expressed as a decimal.)