thursday pod there are twenty kittens on a farm. four are orange, five are black, eight are white,...
TRANSCRIPT
Thursday POD
There are twenty kittens on a farm. Four are orange, five are black, eight are white, and three are gray.
What fraction of the kittens are white? What fraction of the kittens are orange? Write two equivalents for each fraction.
Comparing and Ordering Fractions
SPI 0506.2.9 Compare whole numbers, decimals and fractions using the symbols
<, >, and =.
Objective
We are going to compare whole numbers and fractions using the symbols <, >, and =.
Use your prior knowledge
What have you learned about fractions so far?
You already know how to find equivalent fractions.
Today you will use what you know to compare fractions.
Why do we need to know how to compare fractions? Can you think of a reason? - TCAP Test : )
Think for a minute…Can you think of any jobs or activities that would require you to compare fractions??? Write them down.
Cooking- Measuring
Working with tools- Cabinets, building a fireplace
Working with ribbon- knowing which ribbon is the widest
Working with ribbon
Measurements are often recorded in halves, quarters, and eighths of an inch.
Why would it be important to compare fractions with different denominators when working with inch measurements?
- If you are comparing two measurements, such as ¼in. and 3/8in., you need to be able to compare the fractions to tell which is longer.
*COMPARING FRACTIONS WITH THE SAME DENOMINATORS*
It is easy to compare fractions if they have the same denominator. All you have to do is to compare their numerators.
If two fractions have the same denominator, the
larger fraction is the fraction with larger numerator.
Example1: Which is larger, 2/4 or 3/4 ?
2/4 has only 2 fourth parts
3/4 has 3 fourth parts
Since the denominators are the same, 3/4 is larger than 2/4, because 3 is larger than 2. We write 2/4 < 3/4
Representation
2/4 < 3/4
2/4
3/4
Comparing numbers with common denominators When the denominators are the same, simply
compare the numerator. 2/7 6/7 Which is the greatest?
7/17, 10/17, 16/17
<
Order these fraction from least to greatest.7/17; 16/17; 10/17
Try these
15
19
18
19 19
12
Compare whole numbers first, then fractions.
.
3 3
When there are whole numbers
3 is much more than 18/19
What do you do when the denominators are not the same?
You must find a common denominator. To do this, write out the multiples of each
denominator. The multiples are not the factors. The multiples are the numbers you get when you
multiply the number. For example 6/8 and 4/5
5: 5, 10, 15, 20, 25, 30, 35, 40, 45.....8: 8, 16, 24, 32, 40, 48, 56..... Now let’s see
For example 6/8 and 4/5
5: 5, 10,15, 20, 25, 30, 35, 40, 45.....8: 8, 16, 24, 32, 40, 48, 56.....
Do you see a common multiple???
40 Use 40 as the common denominator.
6/8 x 5/5 = 30/40
4/5 x 8/8 = 32/40 .
Problem: Mr. White has ribbons with the following widths: 7/12 in., ½ in., and 5/8in. He needs to use
the widest ribbon. Which ribbon is the widest? To find the answer we must know how to
compare fractions. Do our denominators match? Based on what you know (prior knowledge)
make an inference. What is the first thing we should do?
Find common denominators!
How do we find common denominators??? Common multiples
Our denominators are 12, 2, 8
2: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24 8: 8, 16, 24, 32, 4012: 12. 24, 36, 48
Is there a common multiple?
Fraction pieces with partner
Let’s Compare!
7/12 6/10<
3/5 4/7<
2/8 3/12=
Using fraction pieces
Come up with a question for a fellow classmate.
Write your problem down. Have the pieces they need to solve the
problem ready, but not put together.
Groups of 4
Number yourselves 1-4 #1 has halves, 3rds, and 11ths #2 has 4ths, 5ths, and 10ths #3 has 6ths, 7ths, and 12ths #4 has 8ths and 9ths
Tell whether the fractions are ordered from least to greatest or greatest to least.
2) 5/8 ; ½ ; 2/10
1) 2/3 ; 7/10 ; 8/9 ; 11/12
3) 7/8 ; ½ ; ¼ ; 1/12
Least to greatest
Greatest to least
Greatest to least
Textbook page 230-231
Do #s 7-12 in your spiral.
When you are finished you may start on homework.
Homework: Worksheet that compares whole numbers and fractions using the symbols <, >, and =.
Before you leave!
Ticket out the door! For extended writing If I was going to share my candy bar with you,
would you rather have 3/8 or 2/5? Write your answer on the “ticket out the
door” and explain why and how you made that decision.
Don’t forget Homework
Worksheet comparing and ordering fractions using symbols.
http://jamit.com.au/htmlFolder/app1005.html
Shark and sock game
http://jamit.com.au/htmlFolder/FRAC1005.html#DiferentDen
explanations