Fractions Addition Subtraction Multiplication and Division 06 March

Fractions Addition, Subtraction, Multiplication and Division 06 March 2021

Fractions – Addition, Subtraction, Multiplication & Division Definitions v. Reciprocals are two numbers whose product is 1. They are also called multiplicative inverses, Examples Arithmetic 3 x 4=1 4 3 4/3 is the reciprocal of 3/4 Algebra a x b =1 b a b/a is the reciprocal of a/b

Fractions – Addition, Subtraction, Multiplication & Division Adding & Subtracting Fractions v. To add or subtract like fractions, (fractions with the same denominator), add or subtract the numerators and write the result over the denominator. Simplify if necessary. Arithmetic Algebra 1+3=4 5 5 5 a+b=a+b c c c

Fractions – Addition, Subtraction, Multiplication & Division Adding & Subtracting Fractions v. To add or subtract unlike fractions (fractions with different denominators), rename the fractions using the LCD, then add or subtract the numerators as with like fractions. Simplify if necessary. Arithmetic 1 + 3 = 5 + 18 = 23 6 5 30 30 30

Fractions – Addition, Subtraction, Multiplication & Division Practice v Add or subtract. Simplify. 2 1. 8 - 2 3 9 9 2. 5 - 3 11 6 8 24 3. 7 + 3 1 5 8 4. 2 - 1 1 3 6 2 5. 3 - 1 7 4 6 12

Fractions – Addition, Subtraction, Multiplication & Division Multiplying Fractions v. To multiply fractions, multiply the numerators and multiply the denominators. Simplify if necessary. v. To multiply mixed numbers, change them to improper fractions first then multiply. Simplify if necessary. Arithmetic 1 x 2= 2 3 5 3 x 5 15 Algebra a x c = ac b d b x d bd

Fractions – Addition, Subtraction, Multiplication & Division Dividing v. To divide by a fraction, change the Fractions second number to the reciprocal (multiplicative inverse) and then multiply. v. To divide mixed numbers, change them to improper fractions first. Simplify if necessary. Arithmetic Algebra 7 ÷ 3 = 7 x 4 = 28 8 4 8 3 24 a ÷ c = a x d = ad b c bc b, c, d ≠ 0

Fractions – Addition, Subtraction, Multiplication & Division Practice v Multiply or Divide. Simplify. 1. 1 x 3 4 4 1/4 2. 2 x 4 3 2 2/3 3. 3 x 51 16 3 4. 4 ÷ 8 5 9 5. 9/10 21÷ 55 3 6 2/5