Lesson 3
Part of a group
![Picture](/uploads/2/0/0/4/20043941/1369913594.png)
Another way to think about fractions is as part of a group. If you have a group of things that are similar in some way you can usually make a fraction out of them.
Look at the flowers to the left. They are all the same type of flower but different colors. I can count 12 flowers in the group that are easy to see. Since I have 12 total flowers, 12 is going to be my denominator.
There are a couple different fractions I can make. If I want to know the fraction of yellow flowers I would count up how many yellow flowers there are to find my numerator: 4. The fraction of flowers that are yellow is 4/12. If I want to know the fraction of flowers that are pink, I know that 8 of the flowers are pink. The fraction of pink flowers in this group is 8/12.
Look at the flowers to the left. They are all the same type of flower but different colors. I can count 12 flowers in the group that are easy to see. Since I have 12 total flowers, 12 is going to be my denominator.
There are a couple different fractions I can make. If I want to know the fraction of yellow flowers I would count up how many yellow flowers there are to find my numerator: 4. The fraction of flowers that are yellow is 4/12. If I want to know the fraction of flowers that are pink, I know that 8 of the flowers are pink. The fraction of pink flowers in this group is 8/12.
The picture below is from one of the bathrooms in my house. There are 5 light bulbs in the mirror. They can be considered a group since they are similar: they are all light bulbs.
Although they are similar, they are not all exactly the same. This is where fractions come in! There are 5 total light bulbs so 5 will be my denominator. If I want to know the fraction of round light bulbs, what would it be? If you said 1/5, you're right! How many light bulbs are oval shaped? The answer is 4/5. How many light bulbs are dark gray? If you said 2/5 then you're on a roll!
The following video will review fractions as part of a whole but near the end the teacher will review fractions as part of group. Focus on the section when he talks about pets!
Practice
Click on the link to Mendel's Magic Math Market below to practice working with fractions as part of a group.
Instructions: Click the start button when the game loads. Read through the instructions and begin the game. Only complete the first two levels; when Mendel starts talking about decimals close the window to come back to this page.
Mendel's Magic Math Market
Instructions: Click the start button when the game loads. Read through the instructions and begin the game. Only complete the first two levels; when Mendel starts talking about decimals close the window to come back to this page.
Mendel's Magic Math Market