Holt CA Course Dividing Fractions and Mixed Numbers NS2.1 Solve problems involving addition, subtraction, multiplication, and division of positive fractions and explain why a particular operation was used for a given situation. Also covered: NS2.2, NS2.4 California Standards

Holt CA Course Dividing Fractions and Mixed Numbers Vocabulary reciprocal multiplicative inverse

Holt CA Course Dividing Fractions and Mixed Numbers Reciprocals can help you divide by fractions. Two numbers are reciprocals or multiplicative inverses if their product is 1. The reciprocal of is 3 because  3 = 1313  3131 = 3333 = 1. Dividing by a number is the same as multiplying by its reciprocal. 6 ÷ 3 =  = 2 same answer reciprocals

Holt CA Course Dividing Fractions and Mixed Numbers You can use this rule to divide by fractions.

Holt CA Course Dividing Fractions and Mixed Numbers Teacher Example 1: Dividing Fractions Divide. Write each answer in simplest form. A ÷ ÷ 2525 = 3737 · 5252 = 3737 · 5 · 2 = or Multiply by the reciprocal of B ÷ ÷ = 3838 · 1 = 3838 · = Multiply by the reciprocal of Simplify.

Holt CA Course Dividing Fractions and Mixed Numbers Student Practice 1: Divide. Write each answer in simplest form. A ÷ ÷ 1212 = 3535 · 2121 = 3535 · 2 · 1 = 6565 or Multiply by the reciprocal of B ÷ ÷ 3 = 3434 · 1 3 = 3434 · Multiply by the reciprocal of 3. 1 = 4 Simplify.

Holt CA Course Dividing Fractions and Mixed Numbers Divide. Write each answer in simplest form. A ÷ ÷ = 17 3 ÷ 5454 = 17 3 · 4545 = or Write mixed numbers as improper fractions. Multiply by the reciprocal of 5454 B ÷ ÷ = 3434 ÷ 5252 = 3 4 · 2525 = 3 · 2 4·5 1 2 = 3 10 Write 2 as an improper fraction Multiply by the reciprocal of Simplify.. Teacher Example 2: Dividing Mixed Numbers

Holt CA Course Dividing Fractions and Mixed Numbers Divide. Write each answer in simplest form. A ÷ ÷ = 11 3 ÷ 3232 = 11 3 · 2323 = 22 9 or Write mixed numbers as improper fractions. Multiply by the reciprocal of 3232 B ÷ ÷ = 3535 ÷ 7575 = 3 5 · 5757 = 3·5 5·7 1 1 = 3 7 Write 1 as an improper fraction Multiply by the reciprocal of Simplify.. Student Practice 2:

Holt CA Course Dividing Fractions and Mixed Numbers Teacher Example 3: Social Studies Application The life span of a golden dollar coin is 30 years, while paper currency lasts an average of 1 years. How many 1212 times longer will the golden dollar stay in circulation? 30 ÷ = 30 1 ÷ 3232 Write the number as an improper fraction. = 30 1 · 2323 Multiply by the reciprocal of = · Simplify = 20 1 or 20 The golden dollar will stay in circulation about 20 times longer than paper currency. ·

Holt CA Course Dividing Fractions and Mixed Numbers Student Practice 3: The average life of a queen ant is approximately 3 years. The life span of a worker ant is year. How many 3737 times longer will the queen ant live? 3 ÷ 3737 = 3131 ÷ 3737 Write the number as an improper fraction. = 3131 · 7373 Multiply by the reciprocal of = · Simplify = 7171 or 7 The queen ant will live 7 times longer than the worker ant. ·