Transcript Decimal and Fraction Addition

Decimal and Fraction Addition
Review Topic 4
Decimal Addition
• Whole numbers have the decimal after the
one place
• Line up the decimal
• Fill in zeros
• Try 5 + 0.3 + 2.12 + 0.243
Common Denominator
• A number that can be divided evenly by
both denominators is a common
denominator
• The smallest common denominator is the
least common denominator
• Find a common denominator
for 7/15 and 5/12
Fraction Addition
• Find the least common denominator
• Raise all fractions to be added to that
denominator
• ADD
• Simplify
Example
•
2 4
8
5  5
3  4  12
13
3
2  2
43
12
5  2  10
3  3
6  2  12
21
10
12
9
3
10  1  11
12
4
•
Example
• r and r2 are
2
not like terms. r  7r  5r
8 6
8
• Just add the
2
first two terms. 3r
28r 5r


• 24 is the LCD
24 24
8
2
2
31r 5r
5r
7

 1 24 r 
24
8
8
Acceptable way to write
• These are the same.
• These are NOT the
same because of the
order of operations.
2x
3
5
2
x
3
3x
4
3
4
5 x