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Lesson 5-3 Comparing and Ordering Fractions. Be sure any late or missing work from last Wednesday is turned in to the tray ASAP!. 5-Minute Review. Write each fraction as a decimal = = = = How many sides does a …… have? Pentagon Nonagon Heptagon Decagon Octagon Hexagon.
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Lesson 5-3Comparing and Ordering Fractions Be sure any late or missing work from last Wednesday is turned in to the tray ASAP!
5-Minute Review • Write each fraction as a decimal = = = = • How many sides does a …… have? Pentagon Nonagon Heptagon Decagon Octagon Hexagon
Math Message on JP 129Complete problems 1-5 • Complete problems 1-5 on JP 129.
Math Message Follow-Up • How did you decide which measurement was closest to the fraction? • How could you use what you know about numerators and denominators to make your decisions without looking at a ruler?
Ordering Fractions (JP 129) ____________ ____________ ____________ ____________ Ordering the fractions from the math message. • Which is least (closest to 0)? • Which is greatest (closest to 1)? • Since and are equally close to , how do we decide where to write them? • Both are eighths, and 5 is more than 3, which means is smaller so it is closer to zero.
Ordering Fractions • Examining numerators and denominators is the first step when comparing and ordering fractions. • What can you describe about these fractions? • All same denominators • So all fractions are the same size • Only the number of pieces (numerators) need to be considered.
Ordering Fractions • Describe the fractions • Numerators are all the same • Now what do we do? • There are the same number of pieces for each fraction. • So only the size of the pieces (denominators) need to be compared. • REMINDER: The smaller the denominator is, the larger the piece is.
Ordering Fractions • Describe the fractions • Two different denominators, and two different unit fractions. • First, compare the unit fractions and . • The smaller denominator is the larger fraction. • The remaining fractions are with in one pieces of 1. • Since is greater than , that makes farther away from 1. • Try 9-12 on your own, then we will review.
Skip Counting with Fractions • A fraction stick is a model for the whole (go back to example). • Each row of the fraction stick chart combines 2 fraction sticks to show the interval from 0-2. • Example: • The third row shows 2 sticks, each divided into thirds. There are 6 pieces in this row, each divided into thirds. • The pieces can be used to count by thirds.
Finding Equivalent Fractions • The fraction-stick chart can be used to find equivalent fractions. • Example: Find equivalent fractions for . • Step1: The denominator is 3, so use the thirds stick to locate the fraction . Count the pieces from left to right. The right edge of the second piece is. • Step 2: Place one edge of a straight edge at , that is, along the right edge of the second piece. The straightedge should be parallel to the sides of the fraction stick chart. Now look for other fraction sticks on the chart along the straightedge.
Finding Equivalent Fractions • On the sixths stick, the straightedge touches the right edge of a piece. Count the sixths-stick pieces from left to right. The straightedge is at the end of the fourth piece, which is . So is equal to . • Look at the ninths. • Look at the twelfths. • Any others?
Comparing Fractions • The fraction stick chart can be used to compare fractions, for example, compare and . • Step 1: The denominator on the first fraction is 9, so use the ninths stick to locate . Count the pieces from left to right. The right edge of the fourth piece is . Place the straightedge along this edge. • Step 2: Locate . Since is to the left of , it is less than . • Complete the rest of journal page 130.
Adding Fractions with Sticks • JP 131
