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This video tutorial explains the rules and applications of multiplying fractions. Learn how to convert mixed numbers to improper fractions, multiply fractions, find area using fractions, and multiply fractions by whole numbers. Practice with interactive games and reinforce concepts using visual models.
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Chapter 7 Multiplying Fractions MAFS.5.NF.2.4; MAFS.5.NF.2.5 ; MAFS.5.NF.2.6 https://www.youtube.com/watch?v=CcDGRLosAf0&feature=youtu.be
Ch 7 Vocabulary 6. simplest form a fraction in which 1 is the only number that can divide evenly into the numerator and the denominator 1. denominator the number below the bar in a fraction that tells how many equal parts are in the whole or in the group 2. equivalent fractions fractions that name the same amount or part 3. mixed number a number that is made up of a whole number and a fraction 4. numerator the number above the bar in a fraction that tells how many equal parts of the whole are being considered 5. product the answer to a multiplication problem
Convert mixed numbers to improper fractions Rules Step 1: Multiply the denominator by the whole number. Step 2: Add the numerator. This is your new numerator. Step 3: New numerator over the original denominator. Example: 3 ¼ = 13/4 2 ½ = 5/2
Khan Academy Video Intro to Multiplying Fractions https://www.khanacademy.org/math/arithmetic/fraction-arithmetic/arith-review-multiply-fractions/v/multiplying-a-fraction-by-a-fraction OF means MULTIPLY
Multiplying Fractions (Old School) ½ x ¾ = 1 x 3 = 3 2 x 4 = 8 Product is ⅜. 2 ¼ x ⅛ = 9/4 x ⅛ = Product is 9/32. Rules Step 1: Multiply the numerators. Step 2: Multiply the denominators. Step 3: Convert to mixed number, if necessary. **If you start with a mixed number, change it to an improper fraction before you multiply.
Multiplying Fractions Cont’d 2. 4/7 x ⅚ = • ¾ x 7/10 = 3. 3 ½ x 5 2/8 = 4. ⅛ x 4 ⅚ =
Multiplying Fractions To Find ARea To find an area of an object, you multiply length x width. • What is the area of the object below? 3/7 unit 2/4 unit 2. Find the area of the figure below. 2/16 Unit ⅞ unit
Multiplying a Fraction by a Whole Number (Old School) ⅔ x 4 = ⅔ x 4/1 = 8/3 or 2 ⅔ Rules Step 1: Put the whole number over 1. 1 is your denominator. Step 2: Solve. **Change improper fraction to mixed numbers, if necessary.
Multiplying fractions by whole numbers cont’d What happens to the product when you... • multiply a whole number by a fraction less than a whole? • Multiply a number greater than one whole (or improper fraction) • 2/6 x 3 = 2. 321 x 1/2 = 3. 34,567 x ⅛ = 4. 526 x 1 ½ =
Fractions Online Game Math Playground https://www.mathplayground.com/fractions_mult.html
Which has a greater value... • Select all the expressions that have a value greater than 1,753. A. 1,753 × ¼ B. 1,753 × 4 C. 1,753 × 12 D. 1,753 × 1 ½ 2. Gavin wants to get a product less than 54,321. Select all the numbers below he can multiply 54,321 by. • 7/12 • 4/4 • 1 ⅕ • 2/9 • 3 • 8/5
Which has a greater value...Student PRACTICE • Select all the expressions that have a value greater than 2,463. A.2,463 × ¼ B.2,463 × 4 C.2,463 × 12 D.2,463 × 1 ½ 2. Wadewants to get a product less than 34,642. Select all the numbers below he can multiply 34,642by. • 8/12 • 6/6 • 2⅕ • 3/7 • 4 • 9/7
Multiplying Fractions with Area Models Rules: (no worries! I will show you what this means) Step 1: Choose a fraction to draw out.(I start with the larger number denominator) Step 2: Shade the numerator. Step 3: Using the same area model, now cut the model into your new denominator. Step 4: Shade in your numerator. Ex: ⅗ x ⅔
Area Models cont’d… StuDEnt PractIce • ¾ x ⅞ = • 3 x ⅓ = Hint* for whole numbers, you draw out separate rectangles. For example, draw three separate rectangles and cut them into thirds. Then shade in ⅓ of each rectangle. 3. ⅖ x ⅔ =
Multiplying Fractions Using a Number Line Rules: Step 1: Draw a number line from 0 to 1. Step 2: Choose a fraction and cut your number line into those sections. Step 3: Using the number line, draw out your other fraction.
Number Lines cont’d • ¾ x ⅞ = • 3 x ⅓ = 3. ⅖ x ⅔ =
Multiplying Fractions using pemdas Order of Operations (PEMDAS) ---> Parentheses, Exponents, Multiplication/Division, Addition/Subtraction Ex 1: 3 × (2/3 − 1/5) Ex 2: 2/3 × (7+9)
Multiplying Fractions using pemdas.. Student Practice Order of Operations (PEMDAS) ---> Parentheses, Exponents, Multiplication/Division, Addition/Subtraction Ex 1: 2 × (3/5 − 2/3) Ex 2: 3/4 × (6+5)