10 3 Comparing Fractions Using Benchmarks Today we

10 -3: Comparing Fractions Using Benchmarks Today we will learn… How to compare fractions using benchmark numbers. WHOLE GROUP LESSON 10 -3

Let’s start by talking about The benchmark fraction 1/2 • Take a 1/2 fraction strip out of your fraction bag. • See if you can find other fractions strips to line up with the 1/2 that would be equal to 1/2 • You can only use fractions strips of the same color at one time • On your whiteboard, record all of the fractions you are able to find that are equal to 1/2 WHOLE GROUP LESSON 10 -3

WHICH FRACTIONS DID YOU FIND THAT WERE ALSO EQUAL TO 1/2? • Talk with your partner, what is the rule for fractions that are equal to 1/2? • Can you think of more fractions that would be equal to 1/2? • Record more fractions that equal 1/2 on your whiteboard. WHOLE GROUP LESSON 10 -3

WE CAN USE THE BENCHMARK 1/2 TO HELP US COMPARE FRACTIONS! • If a fraction is less than 1/2, it is closer to 0. • If a fraction is greater than 1/2 it is closer to 1. EXAMPLE: • Is 3/4 closer to 0 or 1? • Think!- We know that 2/4 is equal to 1/2 • The numerator 3 is bigger than 2. • So, 3/4 must be greater than 1/2 • 3/4 is closer to 1 • Try using your fraction strips to prove this! WHOLE GROUP LESSON 10 -3

NOW TRY ONE WITH YOUR PARTNER! • Is 2/8 closer to 0 or 1? • Think! How many eighths does it take to make 1/2? • Is 2/8 smaller than 1/2 or bigger than 1/2? • Once you know the answer, use your fraction strips to check. WHOLE GROUP LESSON 10 -3

Now, try sorting these fractions on your paper! Closer to 0 Equal to 1/2 Closer to 1 7/8, 2/3, 1/8, 4/8, 3/6, 6/10, 1/4, 1/3, 9/12 WHOLE GROUP LESSON 10 -3

NOW, YOU CAN USE BENCHMARK FRACTIONS TO HELP YOU COMPARE 2 FRACTIONS! 1. Look at the 2 fractions 2. Decide if each fraction is smaller than 1/2, equal to 1/2, or greater than 1/2 3. Use what you know to decide which fraction is greater. Let’s Try it! < 1. I know that 1/4 is less than 1/2 2. I know that 2/3 is greater than 1/2 3. So, 2/3 must be greater than 1/4! WHOLE GROUP LESSON 10 -3

WORK WITH A PARTNER • Use your knowledge of benchmark fractions and your fraction strip pieces to compare these fractions. Now, turn and talk to a new partner and explain to them how you figured out which fraction was greatest. WHOLE GROUP LESSON 10 -3

Draw a Picture to Solve Mr. Park was running a 5 kilometer race. He placed a flag marker at the start line, the finish line, and each kilometer in between. How many flag markers di Mr. Park use? Draw a picture to help you solve the problem. Carefully read the problem. Underline the question. [Bracket] important words and numbers. Eliminate unnecessary information. Solve and check your work. WHOLE GROUP LESSON 10 -3