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Fraction Division Opposite of Multiplication The opposite number: • Invert • Called the reciprocal • 3 4 4 inverted to make 3 To Divide • Invert the second number • Multiply 2 3 2 4 8 5 4 5 3 15 Division as a Complex Fraction 2 4 5 x3 3 4 4 3 2 4 8 x 5 3 15 Denominator goes to one Steps • Change Whole numbers and mixed numbers to improper fractions • Invert the second fraction (the divisor) and multiply • Cancel if you can • Multiply numerator by numerator and denominator by denominator. Examples 1 2 4 • 1 2 4 1 1 1 4 2 1 1 1 4 2 8 • 3 1 2 4 5 3 11 4 5 3 5 4 11 3 5 15 4 11 44 Word Problems Commutative • • • • Multiplication is commutative 3x4 = 4x3 Is division commutative? NO! Division • The order of operation matters • In word problems, be careful what order you write the problem. • The whole being split, cut, sorted, shared, divided, or grouped goes first. • How many pieces or how big goes second. Fran puts 5 1/3 lbs of chocolate in 2/3 lb containers. How many containers? • Chocolate is first as it is split. • Total divided by How Big is How Many. 1 2 16 3 8 1 5 8 3 3 3 2 1 1 • 8 containers. Elements Adapted from WWW.ANIMATIONFACTORY.COM