Adding and Subtracting Fractions

1
Adding and Subtracting Fractions

• You will need
• Fraction factory pieces
• Loose leaf
• pencil

2
Problem 1

• Parties R Fun is a party supply store that is
  closed for inventory.
• The employees at the store are recording all of
  the supplies in the store.
• Kelsey finds 2 open boxes of balloons.
• The boxes are the same size.
• One is ½ full and the other is full.
• Kelsey combines the boxes and records the sum of
  the contents.

Use fraction factory pieces to help determine
the total contents of the combined box.
Explain what you did and then provide diagrams.
3
Represent with Fraction Factory

How can we add together pieces that are
different?
4
Represent with Fraction Factory
Method 1 Represent both with the same piece!


5
Represent with Fraction Factory
Method 2 Compare to one whole!
Combine one half and one third. What area is left
to make one whole?
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Represent with Fraction Factory
Since one sixth is needed to make one whole, One
half and one third combined must be five sixths!
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Problem 2

• Alan is taking inventory of the helium tanks.
• He estimates that one tank is two thirds full and
  one tank is one fourth full.
• What single fraction represents the contents of
  the two tanks together.

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Using fraction factory

How can we add together pieces that are
different?
9
Using fraction factory
Replace with the same piece!


10
Using fraction factory
Method 2 Compare to one whole!
Combine two thirds and one fourth. What area is
left to make one whole?
11
Using fraction factory
Method 2 Compare to one whole!
Since there is one twelfth required to make one
whole, two thirds and one fourth combined must be
11 twelfths