Upload
allyson-lamb
View
212
Download
0
Embed Size (px)
Citation preview
Copyright © 2012, 2009, 2005, 2002 Pearson Education, Inc.
Chapter 2
Fractions
Copyright © 2012, 2009, 2005, 2002 Pearson Education, Inc. Copyright © 2012, 2009, 2005, 2002 Pearson Education, Inc.
Adding and Subtracting Mixed Numbers and the
Order of Operations
2.8
Copyright © 2012, 2009, 2005, 2002 Pearson Education, Inc. Copyright © 2012, 2009, 2005, 2002 Pearson Education, Inc.
Adding Mixed Numbers
When adding mixed numbers, it is best to add the fractions together and then add the whole numbers together.
1 29 2 .6 3
Example:
Add
LCD = 619 642 6
2 2 42 23 2 6
19 622 3
5 611
Add the fractions
first.
Add the whole numbers.
Copyright © 2012, 2009, 2005, 2002 Pearson Education, Inc. Copyright © 2012, 2009, 2005, 2002 Pearson Education, Inc.
Subtracting Mixed Numbers
Subtracting mixed numbers is like adding mixed numbers.
2 1 9 7 .3 8
Example:
Add
LCD = 24
169 2437
24
1 3 37 78 3 24
29 317 8
13 24
2
Subtract the fractions
first.
Subtract the whole numbers.
2 8 169 93 8 24
Copyright © 2012, 2009, 2005, 2002 Pearson Education, Inc. Copyright © 2012, 2009, 2005, 2002 Pearson Education, Inc.
Subtracting Mixed Numbers
1 7 5 3 .12 18
Example:
Add
LCD = 36
3943614336
7 2 143 318 2 36
35 36143 36
251 36
1 3 35 512 3 36
We borrow 1 from 5 to obtain
3 3 39 395 4 1 4 4 .36 36 36 36
3 14We cannot subtract 36 36
so we need to borrow.
Copyright © 2012, 2009, 2005, 2002 Pearson Education, Inc. Copyright © 2012, 2009, 2005, 2002 Pearson Education, Inc.
Order of Operations
Order of Operations1. Perform operations inside any parentheses.2. Simplify any expressions with exponents.3. Multiply or divide from left to right.4. Add or subtract from left to right.
Do first
Do last
Example: Evaluate2
5 2 .8 5
5 48 25
1 12 5
110
Exponents
Multiplication
Copyright © 2012, 2009, 2005, 2002 Pearson Education, Inc. Copyright © 2012, 2009, 2005, 2002 Pearson Education, Inc.
Order of Operations
Example: Evaluate 3 1 5 .4 4 3
3 1 34 4 5
3 1 54 4 3
3 34 20
Express division as multiplication.
Multiply.
15 320 20
Rewrite fractions using the LCD.
18 920 10
Add and simplify.