Chapter 5 Lesson 2Rational Numbers

Pgs. 205-209

Chapter 5 Lesson 2Rational Numbers

Pgs. 205-209

What you will learn (maybe):Write rational numbers as fractions

Identify and Classify rational numbers

What you will learn (maybe):Write rational numbers as fractions

Identify and Classify rational numbers

Vocabulary:Vocabulary: Rational Number (205): A number that can be

written as a fraction. Terminating decimals are rational numbers because they can be written as a fraction with a denominator of 10, 100, 1000

and so on…..

Ex.) 0.75 = 3/4 28 = 28/1 1 1/4 = 5/4

_ -0.3 = - 1/3

Rational Number (205): A number that can be written as a fraction. Terminating decimals are rational numbers because they can be written as a fraction with a denominator of 10, 100, 1000

and so on…..

Ex.) 0.75 = 3/4 28 = 28/1 1 1/4 = 5/4

_ -0.3 = - 1/3

Write Mixed Numbers and Integers as FractionsWrite Mixed Numbers and Integers as Fractions

Write 5 2/3 as a fraction. 2 17 Turn the Mixed # 3 3 into an improper fraction

Write -3 as a fraction

-3 = -3 3 1 1

Write 5 2/3 as a fraction. 2 17 Turn the Mixed # 3 3 into an improper fraction

Write -3 as a fraction

-3 = -3 3 1 1

5 =

or -

Write Terminating Decimals as FractionsWrite Terminating Decimals as Fractions

Write each decimal as a fraction or mixed number in simplest form.

0.48 = 48 See the digit chart on pg. 206 100

Simplify: 12 25

Write each decimal as a fraction or mixed number in simplest form.

0.48 = 48 See the digit chart on pg. 206 100

Simplify: 12 25

6.375 = 6

Simplify: 6

375 1000

3 8

Write Repeating Decimals as FractionsWrite Repeating Decimals as Fractions

Write 0.8 as a fraction in simplest formLet N represent the number: N= 0.888…..Multiply each side by 10 since one digit repeats:10N = 10(.888…)10N = 8.888…..Subtract N from 10N to eleminate the repeating part. 0.888…. 10N = 8.888… - (N = 0.888…) 9N = 8 N = 8 9N = 8 9 9 9

Write 0.8 as a fraction in simplest formLet N represent the number: N= 0.888…..Multiply each side by 10 since one digit repeats:10N = 10(.888…)10N = 8.888…..Subtract N from 10N to eleminate the repeating part. 0.888…. 10N = 8.888… - (N = 0.888…) 9N = 8 N = 8 9N = 8 9 9 9

_

Big Idea! Noteworthy!!Big Idea! Noteworthy!!All rational numbers can be written as terminating orrepeating decimals.

Decimals that do not terminate or repeat are called irrational numbers because they CANNOT be writtenas fractions

Examples of irrational numbers:

Pi = 3.141592654….. ----> digits DO NOT repeat

4.232232223…….---->same blocks of digits DON’T repeat

Refer to the Concept Summary on Pg. 207Refer to the Concept Summary on Pg. 207

Identify all sets to which each number belongs:

-6

2 4/5

0.914114111…

Identify all sets to which each number belongs:

-6

2 4/5

0.914114111…

Integer, Rational

Rational

Irrational

You Try!You Try!

Write each number as a fraction.-2 1/3 10 7 2/3

Write each number as a fraction or mixed number in simplest form.

.8 6.35 -0.7

Write each number as a fraction.-2 1/3 10 7 2/3

Write each number as a fraction or mixed number in simplest form.

.8 6.35 -0.7_

- 7/3 10 1

23 3

4/5 6 7/20 7 9

_