Download Multiply Fractions

Multiplying Fractions and
Mixed Numbers
Unit 5.8
Pages 254-257
Warm Up
Problems
Write each fraction in simplest form.
1.
1
3
1
2
x =
1/6
2.
4
5
3
8
3/10
3.
3
11 x
2 =
6/11
4.
3
8
5
8
x =
x
=
15/64
Solving for Multiplication
using Mixed Numbers
Objective:
Students will be able to multiply
mixed numbers together by changing them
into improper fractions, finding their product,
and then convert it back to a mixed number.
CHALLENGE! I will hand each partner pair 2
whole circles and ¼ of a circle. Your challenge is to
find ½ of the total circles given to you.
How did you find the answer? Write down each step you used to
find the answer and model the steps you wrote using the circles.
We can paper fold to find how to Multiply mixed numbers:
The
reason
our
answer
is
less
To find 1/2 x 1 ½ fold two sheets in
than
the beginning
half
vertically
to show 1 Mixed
½.
number
is the
because
to
show ½ of
1 ½ wewe
foldare
both
sheets in half horizontally.
multiplying
that number by
another
number
is justthat
a
if we label
each foldthat
we make,
of¾a total
whole.
showspiece
we have
squares.
We multiply Mixed Numbers together by getting rid of the
whole first, multiplying the numbers together, and then
putting them all back together again.
Marie and Matt are sharing a large Pizza. Marie cuts
the pizza in half. Matt knows he can’t eat his half of the
pizza, so he cuts it into fourths and eats one piece. What
is the fraction of the whole pizza that Matt did not eat?
Write and equation and solve for this question:
7/8 of the pizza
Find the Product, and simplify it.
Change mixed numbers
to improper fractions
Now find the product
Reduce or change from
improper to proper
fractions.
1 x
3
1 x
3
1
1
2
1
12
1
2
1 x 3 = 3
3
2 6
1 x 3 = 3
3
2 6
(1 x 3)
(2 x 3)
1
2
Find the Product, and simplify it.
Change mixed
numbers to
improper
fractions
Simplify 1st (if
possible) and
find the product
Reduce or change
from improper to
proper fractions.
1 x 2
15 3
1 x 2
15 3
6 x 2 =
5
3
4 =
5
4
5
1 x
14
Find the Product, and simplify it.
NOW YOU TRY
1
13
Change mixed
numbers to
improper
fractions
1 x
14
1
13
Simplify 1st (if
possible) and
find the product
x
=
Reduce or change
from improper to
proper fractions.
=
1
2
3
1 x
4
Find the Product, and simplify it.
NOW YOU TRY
Change mixed
numbers to
improper
fractions
Simplify 1st (if
possible) and
find the product
Reduce or change
from improper to
proper fractions.
1 x
4
x
=
1
13
1
13
=
1
3
12 x
13
Find the Product, and simplify it.
NOW YOU TRY
Change mixed
numbers to
improper
fractions
Simplify 1st (if
possible) and
find the product
Reduce or change
from improper to
proper fractions.
12 x
13
2
x
=
=
5
226
3
28
3
8
When we have a number that
multiplies a mixed number by a whole,
we can use the Distributive Property.
That means you can multiply each
separate addend and still get the
same number.
x
5 3
2
11
Find the Product, and simplify it.
Use the Distributive Property
to solve.
Separate into
parts and wholes
by adding
brackets.
Use the
distributive
property
Add the wholes
and parts back
together, then
reduce.
x
5
x
5 3
5 3
15
x
2
11
10
=
+
11
2
3 11
2
11
5 x 3 = 15
5 x 2 = 10
1 11 11
10
15 11
Find the Product, and simplify it.
Use the Distributive Property
to solve.
Separate into
parts and wholes
by adding
brackets.
Use the
distributive
property
Add the wholes
and parts back
together, then
reduce.
x
5
x
5 4
5 4
20
x
7
10
7
4 10
7
10
5 x 4 = 20
5 x 7 = 35
1 10 10
35
=
+
10
4
85
Find the Product, and simplify it.
Use the Distributive Property
to solve.
Separate into
parts and wholes
by adding
brackets.
Use the
distributive
property
Add the wholes
and parts back
together, then
reduce.
x
2
2 1
2 1
3
x
x
3
5
6
=
+
5
3
15
3
5
2x1=3
2x 3= 6
1 5 5
1
45
Find the Product, and simplify it.
Use the Distributive Property
to solve.
Separate into
parts and wholes
by adding
brackets.
Use the
distributive
property
Add the wholes
and parts back
together, then
reduce.
x
+
3
x
x
3 2
__
=
2
23
2
3
8
A patient was given 3 ½ tablets of medicine. If each tablet
contains 1/20 grains each of medicine, how much grains of
medicine did the patient receive?
= 1/20 g
= 1/20 g
= 1/20 g
= ½ of 1/20 g
7/40 grains of medicine
Homework
5.8 page 256
Due: Friday
 13-24
 42 (14 questions)