Fraction Applications!Created by Katie Graves

What is a Fraction?

Fraction: A Part of a Whole

Fractions have 2 components: Numerator (Top Number)

How many pieces are being discussed Denominator (Bottom Number)

How many pieces something has been divided

N 2D 3

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Who Cares About Fractions?

You should! Fractions are used everyday in… Conversation

That baseball team is only half as good as it was last year!

Baking Add ½ Cup of Sugar, followed by 1/3 Cup Crisco…

Weather Did you hear we got a half inch of rain last night?

Oh my! Music

Half Notes… Whole Notes… Quarter Notes…etc!

Reducing Fractions

Reducing a fraction means that both the numerator and the denominator become smaller

Reduced fractions are equal to the original fraction

When reducing a fraction, both the numerator and the denominator are divided by the same number

For example, can be reduced. If you take 6÷2 for the numerator, and 8÷2, for

the denominator, the reduced fraction is

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Practice Reducing Fractions

How can we reduce…? .

.

.

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Mixed Number Fractions

Mixed Number Fraction: A Whole Number with a Fraction 2 5

What can we do with these types of fractions? Turn them into Improper Fractions

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Turning Mixed Number Fractions into Improper Fractions

Turning Mixed Number Fractions into Improper Fractions Involves 3 Steps: First Step: Multiply the denominator (bottom)

number and the whole number together Second Step: Add the numerator to the result

you got in the first step to obtain the new numerator

Third Step: Put your new nominator on top of the original denominator

2First Step: 2x4=8

Second Step:

8+1=9

Third Step:

5First Step: 5x8=40 Second Step: 40+3=43

Third Step:

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43 89

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Practice Changing Mixed Number Fractions to Improper Fractions

How do we change 2 into an improper fraction?

How do we change 7 into an improper fraction?

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Making Common Denominators

In order to make a common denominator, multiplication takes place.

Our result needs to have the denominators the same.

When multiplying, we multiply each fraction by a different number. However, the denominator and numerator are multiplied by the same number.

For example, if we are trying to make and have a common denominator, we would want both fractions to have 4 as the denominator. We would multiply by 2. Our result would be (1x2)/(2x2)=

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Practice: Common Denominators

Make a common denominator for these fractions: and

and

and Be careful, this problem requires both fractions to

change!

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Multiplying Fractions

When multiplying fractions, one must multiply the numerators together to create a new numerator and the denominators together to create a new denominator

For example, × = =

Real Life Applications: Making a Double or Triple Batch of Chocolate

Chip Cookies

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3×74×8

Practice Multiplying Fractions

× =

× =

Baking Problem: If I am making banana bread for a bake sale

using a recipe for one loaf, and I want to make 2 loafs, what should I do?

If the same recipe calls for cup of sugar, and I want to make 2 loaves, how much sugar do I add?

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Dividing Fractions

When dividing fractions, you first change the division sign to a multiplication sign.

After changing the sign, you invert the second fraction (change the numerator into the denominator and vice-versa) For example, inverted is

Example: ÷

÷ = ×

× =

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Practicing Dividing Fractions

Try these practice problems: ÷

÷ 34

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Activity

Listen to the statements

If the statement applies to you, stand up!

#1: My Favorite Color Is…

Stand up if your favorite color is blue What fraction of the class’s favorite color is blue? If half of the individuals standing changed their

minds and sat down, what fraction of the class’s favorite color is blue?

#2: Something Fishy…

Stand if at some point in your life, you have had a pet fish.

What fraction of the entire class has had a pet fish? What would happen if twice as many people stood

up? What fraction of the class would that be?

#3: Movies

Stand up if you watched a movie this weekend. What fraction of the class stood up? What would happen if we had 3 times as many

individuals stand up? What fraction would that be?

Adding Fractions

When adding fractions, it is important to make sure that both of the fractions have a common (same) denominator For example, we would be able to take +

However, we would not be able to take + without first making a common denominator

When fractions do share a common denominator, we add their numerators and leave the denominator the same For example + = How can we reduce this fraction?

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Practice: Fraction Addition

+ =

+ =

+ = Careful, this question requires an extra step!

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Subtracting Fractions

Subtracting fractions is similar to adding in the sense that using common denominators is essential

When we subtract fractions, we subtract the numerators, while leaving the denominators the same – = =

– = =

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4 - 1 5

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6 - 2 7

Practice Subtracting Fractions

- = After subtracting, can the answer be reduced? If

so, to what?

- = Be careful with the positive/negative signs on

this problem!

- = This problem requires a common denominator.

Don’t forget to find that before solving!

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Fraction Blackjack Game! I will number you into groups of three. Each group will

have their own deck of fraction cards.

The same rules as Blackjack apply, but instead of trying to get to 21, try and get close to 1 without going over.

Each student starts the game by being dealt one card face up. The dealer has to have at least 7/10 or higher before he can stop. The other players’ goal is to get as close to 1 without going over.

Once everyone is satisfied with their hand, all the players show their cards, and the one with the closest total to 1 without going over is the winner.

If the players all go over, the dealer is the automatic winner.

Let’s Review!

Adding and subtracting fractions requires a common denominator and only the numerator changes

Multiplying fractions affects both the numerator and the denominator

Dividing fractions requires the numerator and denominator to be inverted. From there, apply the same steps as in multiplication

Individual Assessments

Next, I’m going to pass out an amazing review worksheet on FRACTIONS!

Try your best!

Feel free to ask questions!