Unit 13 Multiplying and Dividing Mixed Numbers
1. Procedure
Convert 3~ to a fraction.
A. Change mixed numbers to fractions
1. Multiply the denominator by the whole number.
32. - 2x3+1 - 7..
2 -
2. Add this answer to the existing numerator.
3. The answer is the new numerator.
2
- 2
4. Keep original denominator.
B. Multiply and divide as in Unit 11.
1. To multiply: multiply numerators, then multiply denominators
2. To divide: invert divisor, multiply numerators, then multiply denominators
C. Cancel if possible.
D. Reduce answers to lowest terms.
2. Multiplyingmixed numbers
2* X ~
Convert to fractions
Convert to fractions
11
2 x 2~
3
7x2+4 - ~
7 - 7
=~x1
7
112 = 2x1+1=~
2
2
2
2~3 = 3x2+2
2 = §.
3
9~
1
--x~
-7
-£1
1
Cancel
4
% z
=£x%
Multiply numerators
Multiply denominators
1
= g
7 = 1~
7 Reduce
1
-1=
- 1
Cancel
Multiply
Reduce
4
3. Dividing mixed numbers
1
3+6
1~
5'
Convert to fractions
~
116
Convert
3- -1 ~
-- 3 . -1
-1"'7""6
3
=-x1
6
1
1~5 = 5x1+2
= 7..
5
5
Invert
116 = 6x1+1
= 7..
6
6
Multiply
-
7..
.
Invert and cancel
7..
-5"'7""6
- 3x6
- 1x1
= ~=18
1
to fractions
1 A'
6
--X:;.-5
'"
Reduce
=£=11
5
34
Multiply
1
5
Reduce