9.6
Equivalent Fractions and Simplifying Fractions
Also Excel 39
Review on WBs
1. What is the prime factorization of 64?
2. What is 3.8 plus 7.4?
3. What is the LCM of 8 and 6?
4. Write as a whole number: 10/5
Math Notes
Equivalent = equal value
You know that 0.5 = 1/2
We will learn how to find fractions that are equal.
To find equivalent fractions, you must multiply the numerator and the denominator by the same number.
For example,
1/2 x 2 = 2/4, so 1/2 is equivalent to 2/4
3/4 x 2 = 6/8, so 3/4 is equivalent to 6/8
More math notes
You can also divide the numerator and the denominator by the same number to find equivalent fractions. But both numbers in the fraction have to be divisible by the same number with no remainders.
4/6 divided by 2 = 2/3, so 4/6 is equivalent to 2/3
15/35 divided by 5 = 3/7, so 15/35 is equivalent to 3/7
Let's make a fraction strip to prove equivalent fractions.
Fold the paper in 1/2, then 2/4, then 3/6, then 4/8, then 5/10, then 6/12.
Let's Practice on Whiteboards
Fill in the missing fraction:
1. 1/3 = /9
2. 3/10 = 9/
3. 1 3/12 = /4
4. 4 = /6
Math Notes - Heading: Simplest Form
Sometimes we need to make a fraction using the smallest numbers possible. This is called simplest form.
Find the greatest common factor to find the simplest form.
For example in 12/18 - greatest common factor would be 6 so you would divide 12/18 by 6/6 which equals 2/3 the simplest form!
Let's practice on Whiteboards
Change to simplest form:
1. 5/10
2. 39/15
3. 15/18
4. 26/18
5. 28/42
6. 22/30
Building your fraction kit ...
You will need 5 different colors of construction paper.
Orange will represent your whole number block (1),
Purple will represent your halves (1/2),
Pink will represent your fourths (1/4),
Green will represent your eighths (1/8),
Blue will represent your sixteenths (1/16).
You don't need to do anything to orange since it is your whole number (block).
Take the purple and fold it in half, cut it.
Take the pink and fold it in four equal parts and cut it.
Take the green and fold it in eight equal parts and cut it.
Take the blue and fold it in sixteen equal parts and cut it.
You now have a complete fractions kit and are ready to play the game!
Cover Up
This is a game for two or more players. Each player starts with a whole strip. The goal is to be the first to cover the whole strip completely with other pieces of the fraction kit. No overlapping pieces are allowed. Here are the rules:
1. Partners take turns rolling the cube labeled with fractions.
2. The fraction that is faced up on the cube tells you what piece to place on the whole strip.
3. When you are near the end of the game and you or your partner only need a small piece, such as 1/8 or 1/16, rolling 1/2 or 1/4 will not help. You cannot use any of those and you loose your turn, you must roll exactly what you need.