lesson 12 adding fractions different denominators
DESCRIPTION
Fundamental MathematicsTRANSCRIPT
Mr. C Chapter 1: Lesson 12: Adding Fractions with Different Denominator 1
Lesson 12:
Adding Fractions with Different Denominator
Objective
In this lesson, students will learn to add fractions with different denominators.
Steps
1. Find the least common denominator
2. Find the equivalent fraction
3. Add
4. Simplify the solution
Example 1
Find the value of each expression in lowest terms.
5
3
4
3
Step 1: Find the least common denominator
Step 2: Find the equivalent fractions
Fraction 1 Fraction 2
54
20
1fraction ofr Denominato
LCD
Multiply fraction 1 by 5
20
15
5
5*
4
3
Fraction 1 becomes
20
15
45
20
2fraction ofr Denominato
LCD
Multiply fraction 2 by 4
20
12
4
4*
5
3
Fraction 1 becomes
20
12
Step 3: Add
20
27
20
12
20
15
Step 4: Simplify the solution
20
71
Mr. C Chapter 1: Lesson 12: Adding Fractions with Different Denominator 2
Lesson 12:
Adding Fractions with Different Denominator
Practice 1
Find the value of each expression in lowest term
7
6
3
2
9
7
10
5
12
7
8
6
9
5
2
1
12
3
15
13
5
4
10
7
12
5
9
3
3
5
15
9
11
15
10
4
4
1
2
2
7
9
5
6
5
8
15
3
30
10
20
10
17
15
21
4
10
2
8
3
6
5
5
4
25
15
11
4
35
15
22
4
20
15
50
42
4
1
3
1
9
9
14
5
Answers
1) __________
2) __________
3) __________
4) __________
5) __________
6) __________
7) __________
8) __________
9) __________
10) __________
11) __________
12) __________
13) __________
14) __________
15) __________
16) __________
17) __________
18) __________
19) __________
20) __________
21) __________
Mr. C Chapter 1: Lesson 12: Adding Fractions with Different Denominator 3
Lesson 12: Subtracting Fractions with Different Denominator
Steps
1. Find the least common denominator
2. Find the equivalent fraction
3. Subtract
4. Simplify the solution
Example 1
Find the value of each expression in lowest terms.
5
3
4
3
Step 1: Find the least common denominator
Step 2: Find the equivalent fractions
Fraction 1 Fraction 2
54
20
1fraction ofr Denominato
LCD
Multiply fraction 1 by 5
20
15
5
5*
4
3
Fraction 1 becomes
20
15
45
20
2fraction ofr Denominato
LCD
Multiply fraction 2 by 4
20
12
4
4*
5
3
Fraction 1 becomes
20
12
Step 3: Add fractions
20
3
20
12
20
15
Step 4: Simplify the solution
20
3
Mr. C Chapter 1: Lesson 12: Adding Fractions with Different Denominator 4
Lesson 12: Subtracting Fractions with Different Denominator
Practice 1
Find the value of each expression in lowest terms.
7
6
3
2
9
7
10
5
12
7
8
6
9
5
2
1
12
3
15
13
5
4
10
7
12
5
9
3
3
5
15
9
11
15
10
4
4
1
2
2
7
9
5
6
5
8
15
3
30
10
20
10
17
15
21
4
10
2
8
3
6
5
5
4
25
15
11
4
35
15
22
4
20
15
50
42
4
1
3
1
9
9
14
5
Answers
1) __________
2) __________
3) __________
4) __________
5) __________
6) __________
7) __________
8) __________
9) __________
10) __________
11) __________
12) __________
13) __________
14) __________
15) __________
16) __________
17) __________
18) __________
19) __________
20) __________
21) __________
Mr. C Chapter 1: Lesson 12: Adding Fractions with Different Denominator 5
Lesson 12: Adding Mixed Numbers with Different Denominator
Steps
1. Rename mixed numbers as a complex fraction
2. Find the least common denominator
3. Find the equivalent fraction
4. Add
5. Simplify the solution
Example 1
Find the value of each expression in lowest terms.
8
45
15
32
Step 1: Rename mixed numbers as a complex fraction
8
44
15
33
8
45
15
32
Step 2: Find the least common denominator
Step 3: Find the equivalent fractions
Fraction 1 Fraction 2
815
120
1fraction ofr Denominato
LCD
Multiply fraction 1 by 30
120
264
8
8*
15
33
Fraction 1 becomes
120
264
158
120
2fraction ofr Denominato
LCD
Multiply fraction 2 by 4
120
660
15
15*
8
44
Fraction 1 becomes
120
660
Step 4: Add
10
77
5*3*2*2*2
11*7*3*2*2
120
924
120
660
120
264
Step 5: Simplify the solution
10
77
Mr. C Chapter 1: Lesson 12: Adding Fractions with Different Denominator 6
Lesson 12: Adding Mixed Numbers with Different Denominator
Practice 1
Find the value of each expression in lowest term
7
62
3
21
9
73
10
52
12
74
8
63
9
53
2
14
12
35
15
133
5
47
10
75
12
54
9
37
3
57
15
94
11
1510
10
47
4
14
2
22
7
98
5
66
5
810
15
38
30
103
20
101
17
157
21
45
10
23
8
39
6
52
5
42
25
15
5
41
35
152
22
46
20
158
50
4210
4
13
3
111
9
99
14
59
Answers
1) __________
2) __________
3) __________
4) __________
5) __________
6) __________
7) __________
8) __________
9) __________
10) __________
11) __________
12) __________
13) __________
14) __________
15) __________
16) __________
17) __________
18) __________
19) __________
20) __________
21) __________
Mr. C Chapter 1: Lesson 12: Adding Fractions with Different Denominator 7
Lesson 12: Subtracting Mixed Numbers with Different Denominator
Steps
1. Rename mixed numbers as a complex fraction
2. Find the least common denominator
3. Find the equivalent fraction
4. Subtract
5. Simplify the solution
Example 1
Find the value of each expression in lowest terms.
8
452
Step 1: Rename mixed numbers as a complex fraction
6
34
1
2
6
452
Step 2: Find the least common denominator
Step 3: Find the equivalent fractions
Fraction 1 Fraction 2
61
6
1fraction ofr Denominato
LCD
Multiply fraction 1 by 6
6
12
6
6*
1
2
Fraction 1 becomes
6
12
16
6
2fraction ofr Denominato
LCD
Multiply fraction 2 by 4
6
34
1
1*
6
34
Fraction 1 becomes
6
34
Step 4: Add
3
11
3*2
11*2
6
22-
6
34
6
12
Step 5: Simplify the solution
3
23
Mr. C Chapter 1: Lesson 12: Adding Fractions with Different Denominator 8
Lesson 12: Subtracting Mixed Numbers with Different Denominator
Practice 1
Find the value of each expression in lowest term
7
62
3
23
9
72
10
52
12
7
8
61
9
5310
12
35
5
133
7
49
8
71
12
54
9
37
25
57
15
94
12
1510
10
417
4
14
2
212
7
98
5
69
5
810
5
38
6
53
2
111
7
157
21
45
10
23
8
39
6
52
5
42
25
15
5
41
3
152
5
46
20
158
50
4210
4
13
3
19
9
98
14
59
Answers
1) __________
2) __________
3) __________
4) __________
5) __________
6) __________
7) __________
8) __________
9) __________
10) __________
11) __________
12) __________
13) __________
14) __________
15) __________
16) __________
17) __________
18) __________
19) __________
20) __________
21) __________
Mr. C Chapter 1: Lesson 12: Adding Fractions with Different Denominator 9
Lesson 12: Test Your Knowledge Name:______________
Date:_______________
Practice 1
Solve each problem. Simplify the solution to lowest terms.
1.
8
3
2
4
2.
30
6
25
15
3.
40
242
30
253
4.
18
22
12
36
5.
27
23
18
98
6.
4
3
9
5
7.
6
41
16
145
8.
3
204
7
27
9.
2
3
12
43
10.
39
21
3
13
11.
10
1
16
4
12.
6
43
2
34
13.
15
130
5
101
14.
2
114
12
96
15.
20
1212
12
87
16.
8
282
28
149
17.
8
23
40
322
18.
30
151
35
20
19.
5
22
10
8
20.
44
23
4
14
21.
16
100
15
301
Answers
1) __________
2) __________
3) __________
4) __________
5) __________
6) __________
7) __________
8) __________
9) __________
10) __________
11) __________
12) __________
13) __________
14) __________
15) __________
16) __________
17) __________
18) __________
19) __________
20) __________
21) __________