Slide 1 Copyright © 2015, 2011, 2008 Pearson Education, Inc. Chapter 2 The Whole Numbers Chapter 1

Slide 2 Copyright © 2015, 2011, 2008 Pearson Education, Inc. Multiplying Whole Numbers and Area Section1.6

Slide 3 Copyright © 2015, 2011, 2008 Pearson Education, Inc. Multiplying Whole Numbers Multiplication is repeated addition but with different notation = The  is called a multiplication sign.

Slide 4 Copyright © 2015, 2011, 2008 Pearson Education, Inc. Properties Multiplication Property of 0 The product of 0 and any number is 0. For example, 5  0 = 0 and 0  8 = 0. Multiplication Property of 1 The product of 1 and any number is that same number. For example, 1  9 = 9 and 7  1 = 7.

Slide 5 Copyright © 2015, 2011, 2008 Pearson Education, Inc. Example Multiply. a. 4 × 1 b. 0(5) c. 1(52) d. (76)(0) = 4 = 0 = 52 = 0

Slide 6 Copyright © 2015, 2011, 2008 Pearson Education, Inc. Properties Commutative Property of Multiplication Changing the order of two factors does not change their product. For example, 4  3 = 12 and 3  4 = 12. Associative Property of Multiplication Changing the grouping of factors does not change their product. For example, (2  3)  4 = 2  (3  4).

Slide 7 Copyright © 2015, 2011, 2008 Pearson Education, Inc. Properties Distributive Property Multiplication distributes over addition. For example, 2(3 + 4) = 2   4

Slide 8 Copyright © 2015, 2011, 2008 Pearson Education, Inc. Example Rewrite 4(5 + 6) using the distributive property. 4(5 + 6) = 4   6

Slide 9 Copyright © 2015, 2011, 2008 Pearson Education, Inc. Multiplying Whole Numbers Example: Use the distributive property to multiply 3 and 79. Write 79 in expanded form. Apply the Distributive Property. Multiply. Add.

Slide 10 Copyright © 2015, 2011, 2008 Pearson Education, Inc. Multiplying Whole Numbers Example: Multiply 624 by 3.

Slide 11 Copyright © 2015, 2011, 2008 Pearson Education, Inc. Multiplying Whole Numbers Example: Multiply 91 by 72.

Slide 12 Copyright © 2015, 2011, 2008 Pearson Education, Inc. Multiplying Whole Numbers Ending in Zero(s) Example: Multiply 3 by  9000 = 3  9  1000 = (27)  1000 = 27,000

Slide 13 Copyright © 2015, 2011, 2008 Pearson Education, Inc. Finding the Area of a Rectangle Example: Find the area of the following rectangle. 12 inches 4 inches

Slide 14 Copyright © 2015, 2011, 2008 Pearson Education, Inc. Solving Problems by Multiplying Key Words or Phrases ExampleSymbols Multiply Multiply 3 by 4 3  4 Product The product of 5 and 10 5  10 Times 6 times 4 6  4

Slide 15 Copyright © 2015, 2011, 2008 Pearson Education, Inc. Example A particular color printer can print 21 pages per minute. How many pages can it print in 25 minutes? Pages per minute  Number of minutes = 21  25

Slide 16 Copyright © 2015, 2011, 2008 Pearson Education, Inc. Example A professor of history purchased DVDs and CDs through a club. Each DVD was priced at $11 and each CD cost $9. He bought eight DVDs and five CDs. Find the total cost of the order. Price of 8 DVDs = (11)(8) = $88 Price of 5 CDs = 5(9) = $45 Total = $88 + $45 = $133

Slide 17 Copyright © 2015, 2011, 2008 Pearson Education, Inc. Example If an average page in a book contains 163 words, estimate, rounding each number to the nearest hundred, the total number of words contained on 391 pages. 163 rounds to rounds to (400) = 80,000 words