Warm Up Problem There are 300 students in the middle school. 23% brought fruit as a snack. Find the number of students who brought fruit.

Multiply Mixed Numbers Lesson 4-4

Objectives I can convert a mixed number to an improper fraction. I can multiply mixed numbers.

Mixed # to Improper Fraction Step 1: Multiply the denominator and the whole number. Step 2: Add the numerator. Step 3: Write the fraction with the new numerator. The denominator stays the same. Example: 4 2 3 4 x 2 = 8 8 + 3 = 11 11 3

Example 1 Find 1 3 x 1 3 4 . Write in simplest form. Write the mixed number as an improper fraction. 1 3 4 = 7 4 Multiply across: 1 3 x 7 4 = 7 12

Example 2 Find 5 1 2 x 1 3 . Write in simplest form. Write the mixed number as an improper fraction. 5 1 2 = 11 2 Multiply across: 11 2 x 1 3 = 11 6 Simplify: 11 6 = 1 5 6

Got It? 1) 2 3 x 2 1 2 2) 3 8 x 3 1 3

Example 3 Find 1 7 8 x 3 1 3 . Write in simplest form. Write BOTH mixed numbers as improper fractions. 1 7 8 = 15 8 3 1 3 = 10 3 Multiply (simplify first): 15 5 8 4 x 10 5 3 1 = 25 4 Simplify: 25 4 = 6 1 4

Got It? 3) 1 2 3 x 2 4 7

Example 4 The Hoover Dam contains 4 1 2 million cubic yards of concrete. The Grand Coulee Dam, in Washington state, contains 2 2 3 times as much concrete. How much concrete does it contain? Find 4 1 2 x 2 2 3 . 4 1 2 = 9 2 2 2 3 = 8 3 Multiply: 9 3 2 1 x 8 4 3 1 = 12 1 or 12 There are 12 million cubic yards of concrete in the Grand Coulee Dam.

Got It? Mr. Wilkins is laying bricks to make a rectangular patio. The area he is covering with bricks is 15 1 2 feet by 9 3 4 feet. What is the area of the patio?

What if… …you multiply a fraction by a fraction? It is a fraction (less than 1) …you multiply a fraction by 1? It is that fraction (anything multiplied by 1 is just that number) …you multiply a fraction by a mixed number? It equals a mixed number (greater than 1)