Fractions of Sets

By Mr. Bales

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 example…parts of a set, and division of whole numbers by whole numbers.

Introduce

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

Introduce

• Let’s 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)

• Let’s try the same thing, but this time let’s look at all those that have short sleeves.

• What fraction of the group is wearing short sleeves?

Example•Before we practice together,

let’s have Mrs. Verughese show us an example of how to find a fraction of a set!!

•Mrs. Verughese!!•Now a Game!!

Let’s 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”.

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

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

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

Now Let’s Combine Generalizations with

FractionsTime to Move!!

Assignment

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

Homework