Copyright © 2011 Pearson Education, Inc. Publishing as Prentice Hall. 2.4 Multiplying Fractions and Mixed Numbers

Martin-Gay, Basic Mathematics, 4e 22 Copyright © 2011 Pearson Education, Inc. Publishing as Prentice Hall. Multiplying Fractions To multiply two fractions, multiply the numerators and multiply the denominators. If a, b, c, and d represent positive whole numbers we have P

Martin-Gay, Basic Mathematics, 4e 33 Copyright © 2011 Pearson Education, Inc. Publishing as Prentice Hall. Examples Multiply. a. b. c. P

Martin-Gay, Basic Mathematics, 4e 44 Copyright © 2011 Pearson Education, Inc. Publishing as Prentice Hall. Examples Multiply and simplify. a. b. P

Martin-Gay, Basic Mathematics, 4e 55 Copyright © 2011 Pearson Education, Inc. Publishing as Prentice Hall. Practice Problems Multiply and simplify P No common factors No common Factors Multiplying Fractions

Martin-Gay, Basic Mathematics, 4e 66 Copyright © 2011 Pearson Education, Inc. Publishing as Prentice Hall. Practice Problems Multiply and simplify P 142 Multiplying Fractions

Martin-Gay, Basic Mathematics, 4e 77 Copyright © 2011 Pearson Education, Inc. Publishing as Prentice Hall. Multiplying Fractions and Mixed Numbers or Whole Numbers Multiplying Fractions and Mixed Numbers of Whole Numbers To multiply with mixed numbers or whole numbers, first write any mixed or whole numbers as fractions and then multiply as usual. P 143

Martin-Gay, Basic Mathematics, 4e 88 Copyright © 2011 Pearson Education, Inc. Publishing as Prentice Hall. Examples Multiply. a. b. P 143

Martin-Gay, Basic Mathematics, 4e 99 Copyright © 2011 Pearson Education, Inc. Publishing as Prentice Hall. Example Multiply. P 143

Martin-Gay, Basic Mathematics, 4e 10 Copyright © 2011 Pearson Education, Inc. Publishing as Prentice Hall. Practice Problems Multiply and simplify P Multiplying Fractions and Mixed Numbers or Whole Numbers

Martin-Gay, Basic Mathematics, 4e 11 Copyright © 2011 Pearson Education, Inc. Publishing as Prentice Hall. Example Multiply. Check by estimating. Let’s check by estimating. rounds to 2, rounds to 1, and 2 · 1 = 2. The estimate is close to the exact value, so our answer is reasonable. P 144

Martin-Gay, Basic Mathematics, 4e 12 Copyright © 2011 Pearson Education, Inc. Publishing as Prentice Hall. Example An estimate for the measure of an adult’s wrist is of the waist size. If Jorge has a 34-inch waist, estimate the size of his wrist. Jorge’s wrist is about inches. P 145

Martin-Gay, Basic Mathematics, 4e 13 Copyright © 2011 Pearson Education, Inc. Publishing as Prentice Hall. Practice Problem 14 similar SOLUTION About 1/3 of all plant and animal species in the United States are at risk of becoming extinct. There are 20,439 known species of plants and animals in the United States. How many species are at risk of extinction? P 145 Solving Problems by Multiplying Fractions

Martin-Gay, Basic Mathematics, 4e 14 Copyright © 2011 Pearson Education, Inc. Publishing as Prentice Hall. DONE

Martin-Gay, Basic Mathematics, 4e 15 Copyright © 2011 Pearson Education, Inc. Publishing as Prentice Hall. DONE