Page 168 - NUMINO TG_5A
P. 168
10Multiply Mixed Numbers Unit
2 . Multiply. 2. To multiply a group of mixed numbers,
Example students should convert to improper
1 1 1 1 1 1 = 31 41 5 = 1 1 5 fractions, look to factor, and then solve as
2 3 4 2 3 4 2 1 1
normal. 1 1 1
2 3 4
1 1 5 Example: 1 1 1
2
=
= 2 1 Step 1: Convert the mixed numbers to
2
improper fractions. 3 4 5
2 3 4
a. Step 2: Look for common factors and factor
1 1 2 1 3 1 = 3 7 16 = 56 = 11 1 the fractions.
2 3 5 2 3 5 5 5
145
214
115
211
Step 3: Multiply and simplify
1155
2112
b. 3 1 2 1 2 1 2 1 2 =3 5 7 9 11 = 11 5 2 1
3 5 7 9 3 5 7 9 2 2
Have students solve the problems using this
method.
10. Multiply Mixed Numbers 95
For students who are having difficulty combining these methods, offer some suggestions.
Convert to improper fractions by asking yourself how many parts each “1” of the mixed number contains,
then add or multiply accordingly.
Factor the given fractions one set at a time. Do not attempt to factor the first and third fractions right away.
Factor the first and second fractions, then the second and third fractions, and so on.
When multiplying, multiply all the numerators first then all the denominators.
When simplifying, divide the numerator by the denominator and don’t forget to include the remainder as a
fraction.
5A Unit 10 151
2 . Multiply. 2. To multiply a group of mixed numbers,
Example students should convert to improper
1 1 1 1 1 1 = 31 41 5 = 1 1 5 fractions, look to factor, and then solve as
2 3 4 2 3 4 2 1 1
normal. 1 1 1
2 3 4
1 1 5 Example: 1 1 1
2
=
= 2 1 Step 1: Convert the mixed numbers to
2
improper fractions. 3 4 5
2 3 4
a. Step 2: Look for common factors and factor
1 1 2 1 3 1 = 3 7 16 = 56 = 11 1 the fractions.
2 3 5 2 3 5 5 5
145
214
115
211
Step 3: Multiply and simplify
1155
2112
b. 3 1 2 1 2 1 2 1 2 =3 5 7 9 11 = 11 5 2 1
3 5 7 9 3 5 7 9 2 2
Have students solve the problems using this
method.
10. Multiply Mixed Numbers 95
For students who are having difficulty combining these methods, offer some suggestions.
Convert to improper fractions by asking yourself how many parts each “1” of the mixed number contains,
then add or multiply accordingly.
Factor the given fractions one set at a time. Do not attempt to factor the first and third fractions right away.
Factor the first and second fractions, then the second and third fractions, and so on.
When multiplying, multiply all the numerators first then all the denominators.
When simplifying, divide the numerator by the denominator and don’t forget to include the remainder as a
fraction.
5A Unit 10 151
