Fractions Part 2 Multiplication of Fractions by Ms. Zeichick Fourth Grade

Real Life Application-When do We Multiply Fractions? Your family eats 1/8 of 1/2 of a left over wedding cake. What do use? 1/8 of 1/2 or 1/8 x 1/2 E Skill

When You Would Multiply a Fraction Times a Fraction Jose had already read 1/2 of his novel. Today he read 1/12 of the 1/2 left. How much of the book has he read? 1/12 of 1/2 or 1/12 x 1/2 E SKILL

Multiplying Fractions Conceptual Understanding When you multiply two fractions that are between 0 and 1 the product is smaller than both fractions. ½ x ¾ = 3/8 Look at the diagram on the next slide to understand why. E SKILL

Multiplying Fractions Conceptual Understanding ½ x ¾ = 3/8 ¼ ¼ ¼ ¼ 1/8 1/8 1/8

Let’s Model Together 2/3 of 1/4 = First, let us fold the paper into a half then another half . Shade 1 on the boxes red. Next, we will turn the paper around and fold the paper in to make three rows. We will shade two of three columns blue. Now we have 12 boxes and two of them are double shaded. This equals 2/12

How to Find a Fraction of a Fraction The first thing to remember is “of” means multiply in mathematics. of x =

How to Find a Fraction of a Fraction Step 1 - When you see a fraction problem you know when you read “of” in the problem you multiply. 1 4 x of 2 9

How to Find a Fraction of a Fraction Step 2 – Multiply your numerators straight across. 1 x 4 4 = 2 9

How to Find a Fraction of a Fraction Step 3 – Then multiply your denominators straight across. 1 x 4 4 = 2 9 18

How to Find the Fraction of a Fraction-Simplify Step 4 – Simplify your answer. In this case we reduce. 1 x 4 4 2 2 ÷ = = 2 9 18 2 9 ÷

Multiply and Simplify 1 9 9 3 3 of ÷ x = = 6 5 30 3 10 ÷

Multiply and Simplify 8 3 24 12 2 of x ÷ = = 9 4 36 12 3 ÷

Enrichment-Improper Fractions 4 7 4 28 of x = 6) 28 2 3 6 24 4 2 2 ÷ 4 4 = 4 6 2 3 ÷

Multiply and Simplify 3 3 9 27 3 8 of x = 8) 4 2 8 27 24 3

Multiply and Simplify 2 7 8 56 9 6 of x = 6) 3 2 6 56 54 2 2 1 ÷ 9 = 9 2 6 ÷ 2 3

Multiply and Simplify Super job! 4 4 3 12 1 8 of x = 8) 2 4 8 12 8 4 4 1 ÷ = 1 1 4 8 4 2 ÷