2-9 Equivalent Fractions and Mixed Numbers Warm Up Warm Up Lesson Presentation Lesson Presentation Problem of the Day Problem of the Day Lesson Quizzes Lesson Quizzes
Dec 17, 2015
2-9 Equivalent Fractions and Mixed Numbers
Warm UpWarm Up
Lesson PresentationLesson Presentation
Problem of the DayProblem of the Day
Lesson QuizzesLesson Quizzes
2-9 Equivalent Fractions and Mixed Numbers
Warm UpName a common factor for each pair.
1. 5 and 10 2. 9 and 12
3. 20 and 24 4. 10 and 14
5. 6 and 8 6. 8 and 15
5 3
4 2
2 1
Possible answers:
2-9 Equivalent Fractions and Mixed Numbers
Problem of the Day
Find a number less than 100 for which all three statements are true:• Divide by 3. Remainder of 2.• Divide by 4. Remainder of 3.• Divide by 5. Remainder of 4.
59
2-9 Equivalent Fractions and Mixed Numbers
Learn to identify, write, and convert between equivalent fractions and mixed numbers.
2-9 Equivalent Fractions and Mixed Numbers
In some recipes the amounts of ingredients are given as fractions, and sometimes those fractions do not equal the fractions on a measuring cup. Knowing how fractions relate to each other can be very helpful.
Different fractions can name the same number.
35 = = 15
256
10
2-9 Equivalent Fractions and Mixed Numbers
=
To create fractions equivalent to a given fraction, multiply or divide the numerator and denominator by the same number.
In the diagram = . These are called
equivalent fractions because they are different expressions for the same nonzero number.
35
610
1525
2-9 Equivalent Fractions and Mixed Numbers
Find two fractions equivalent to .
Additional Example 1: Finding Equivalent Fractions
57
5 · 27 · 2
= 1014
Multiply numerator and denominator by 2.
5 · 37 · 3 = 15
21Multiply numerator and denominator by 3.
2-9 Equivalent Fractions and Mixed Numbers
Check It Out: Example 1
Find two fractions equivalent to .
6 · 212 · 2
= 1224
Multiply numerator and denominator by 2.
6 ÷ 212 ÷ 2
= 36
Divide numerator and denominator by 2.
612
2-9 Equivalent Fractions and Mixed Numbers
A fraction is in simplest form when the numerat or and denominator are relatively prime. Relatively prime numbers have no common factors other than 1.
2-9 Equivalent Fractions and Mixed Numbers
Write the fraction in simplest form.
Additional Example 2: Writing Fractions in Simplest Form
1824
Find the GCF of 18 and 24.
The GCF is 6 = 2 • 3.
=1824
Divide the numerator and denominator by 6.
18 = 2 • 3 • 3
24 = 2 • 2 • 2 • 3
18 ÷ 624 ÷ 6 = 3
4
2-9 Equivalent Fractions and Mixed Numbers
Write the fraction in simplest form.
Check It Out: Example 2
1545
Find the GCF of 15 and 45.
The GCF is 15 = 3 • 5.
=1545
Divide the numerator and denominator by 15.
15 = 3 • 5
45 = 3 • 3 • 5
15 ÷ 1545 ÷ 15 = 1
3
2-9 Equivalent Fractions and Mixed Numbers
Determine whether the fractions in each pair are equivalent.
Additional Example 3A: Determining Whether Fractions are Equivalent
and 46
2842
Both fractions can be written with a denominator of 3.
46 = 4 ÷ 2
6 ÷ 2 = 23
2842
= 28 ÷ 1442 ÷ 14 = 2
3
The numerators are equal, so the fractions are equivalent.
2-9 Equivalent Fractions and Mixed Numbers
Additional Example 3B: Determining Whether Fractions are Equivalent
Determine whether the fractions in each pair are equivalent.
and 610
2025
Both fractions can be written with a denominator of 50.
= 6 · 510 · 5 = 30
502025
= 20 · 225 · 2 = 40
50The numerators are not equal, so the fractions are not equivalent.
610
2-9 Equivalent Fractions and Mixed Numbers
85= 13
5
85 is an improper
fraction. Its numerator is greater than itsdenominator.
1 35
is a mixednumber. Itcontains both awhole numberand a fraction.
An improper fraction is a fraction where the numerator is than or equal to the denominator.
Remember!
2-9 Equivalent Fractions and Mixed Numbers
A. Write
Additional Example 4: Converting Between Improper Fractions and Mixed Numbers
135 as a mixed number.
First divide the numerator by the denominator.
135
= 2 35
Use the quotient and remainder to write a mixed number.
B. Write 7 23 as an improper fraction.
First multiply the denominator and whole number,and then add the numerator.
2233
+
= 3 · 7 + 23 = 23
3
Use the result to write the improperfraction.
2-9 Equivalent Fractions and Mixed Numbers
Check It Out: Example 4
A. Write 156 as a mixed number.
First divide the numerator by the denominator.
156
= 2 36
Use the quotient and remainder to write a mixed number.
B. Write 8 13 as an improper fraction.
First multiply the denominator and whole number,and then add the numerator.
113388
+
= 3 · 8 + 13 = 25
3
Use the result to write the improperfraction.
12
= 2
2-9 Equivalent Fractions and Mixed Numbers
Standard Lesson Quiz
Lesson Quizzes
Lesson Quiz for Student Response Systems
2-9 Equivalent Fractions and Mixed Numbers
Lesson Quiz
1. Write two fractions equivalent to .
2. Determine if and are equivalent.
3. Write the fraction in simplest form.
4. Write as a mixed number.
5. Write 4 as an improper fraction.
1224
1648
37
317
182
12,
36
178
5 12
4 10
13
no
2-9 Equivalent Fractions and Mixed Numbers
1. Identify two fractions equivalent to .
A. Possible answer: ,
B. Possible answer: ,
C. Possible answer: ,
D. Possible answer: ,
Lesson Quiz for Student Response Systems
12 60
1
5
3 15
1
5
3 5
1
6
3 18
1 10
3 30
2-9 Equivalent Fractions and Mixed Numbers
2. Identify the fractions that are not equivalent.
A. , C. ,
B. , D. ,
Lesson Quiz for Student Response Systems
3 16
6 32
3 16
7 10
7 10
14 20
3 7
15 35
2-9 Equivalent Fractions and Mixed Numbers
3. Which of the following represents the fraction in simplest form?
A. C.
B. D.
Lesson Quiz for Student Response Systems
1 5
1 4
1 3
1 2
15 30
2-9 Equivalent Fractions and Mixed Numbers
4. Which of the following represents as a mixed number?
A. 5 C. 3
B. 4 D. 2
Lesson Quiz for Student Response Systems
1 6
1 6
1 6
1 6
19 6