This document discusses rules for adding and subtracting fractions and mixed numbers with different denominators. It provides examples for: 1) Adding fractions by finding the least common denominator (LCD), converting the fractions to equivalent fractions with the LCD, and adding the numerators. 2) Subtracting fractions using the same process of finding the LCD, converting to equivalent fractions, and subtracting the numerators. 3) Adding and subtracting mixed numbers by first combining the whole numbers and then applying the fraction rules.

1. ADDING AND SUBTRACTING
DISSIMILAR FRACTIONS AND
MIXED NUMBERS

2. Rules in Adding and Subtracting
Dissimilar Fractions
 get the LCD or Least Common Denominator
 divide the LCD and the first denominator
and multiply the quotient to the
numerator and do the same to the second
fraction
 reduce the fraction to its lowest form if
possible

3. Examples:
1.)
1
3
+
1
2
=
2+3
6
=
5
6
2.)
3
4
−
2
3
=
9−8
12
=
1
12
3.)
6
8
−
2
4
=
6−4
8
=
2
8
or
1
4

4.  add or subtract the whole numbers
 then, find the LCD or Least Common Denominator
 divide the LCD and the first denominator and
multiply the quotient to the numerator and do
the same to the second fraction
 reduce the fraction to its lowest form if possible
Rules in Adding and Subtracting Mixed
Numbers with Different Denominators

5. 1.) 3
1
2
+ 2
1
3
= 3 + 2 +
3+2
6
= 5
5
6
2.) 9
3
4
− 5
2
3
= 9 − 5 +
9−8
12
= 4
1
12
Examples: