Fractions of Sets

1
Fractions of Sets

• By Mr. Bales

2
Objective

• By the end of this lesson, you will be able to
  identify, read, write, and model fractions for
  parts of a set.
• Standard 4NS1.5 - Students will explain different
  interpretations of fractions, for exampleparts
  of a set, and division of whole numbers by whole
  numbers.

3
Introduce

• If you had twenty pennies, and I asked you to
  show 1/2 of the pennies, how many pennies would
  that be?

4
Introduce

• Lets practice using fractions in our class.
• Everyone wearing pants head to the back of the
  room on the tile.
• What is the fraction of students wearing pants?
  (remember the number for what you are looking for
  goes on top of the fraction, and the total number
  of students goes on the bottom of the fraction)
• Lets try the same thing, but this time lets
  look at all those that have short sleeves.
• What fraction of the group is wearing short
  sleeves?

5
Example

• Before we practice together, lets have Mrs.
  Verughese show us an example of how to find a
  fraction of a set!!
• Mrs. Verughese!!
• Now a Game!!

6
Lets Practice Making Fractions of a Set

• In the middle of your table you will find a bunch
  of cubes. Please take out 12 cubes and place on
  your desk.
• Next, count out 1/3 of those cubes.
• Note - The whole is 12 cubes, not one cube.
• Divide the cubes into three equal groups, or
  three fair shares.

7
Sharing

• Natalie, how much is the whole?
• The cubes in each group represent what fraction
  of all the cubes?
• How many cubes are in each group?
• How much is 1/3 of 12 cubes?
• One way to find 1/3 of 12 is to first divide
  the cubes into three equal groups. Then, you want
  only 1 of those groups. How many is in that
  group?
• 4

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More Practice

• Now using only 8 cubes instead of 12 show the
  following
• 1/4 of 8
• 1/2 of 8
• 3/4 of 8
• 6/8 of 8

• Now using 14 cubes show the following
• 1/7 of 14
• 3/7 of 14
• 5/7 of 14
• 14/14 of 14

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Bales Bucks

• How much is
• 1/4 of 32 cents
• 1/5 of 30 cents
• 2/3 of 27 cents
• 2/4 of 32 cents
• 2/5 of 30 cents

• 5/6 of 30 cents
• 3/4 of 32 cents
• 4/5 of 30 cents
• 3/8 of 40 cents
• 6/7 of 42 cents
• 4/5 of 50 cents

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Now Lets Combine Generalizations with Fractions

• Time to Move!!

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Assignment

• Page 512 - s 8 - 17
• Get them all correct - No Math Homework