Bell Ringer Monica and Ryan shared 18 cookies. Monica ate 1/6 of the cookies. Ryan ate 1/3 of the cookies. How many cookies were left? 1/6 of the cookies! 1/3 of the cookies!
Adding and Subtracting Fractions A Journey into the wonderful world of fractions…
Lowest Common Multiple Find the multiples of each number and the first one in common is the lowest common multiple. What is the LCM of 5 and 6? 6 – 6, 12, 18, 24, 30, 36, 42, 48 5 – 5, 10, 15, 20, 25, 30, 35, 40
Lowest Common Multiple SAMPLE: Find the lowest common multiple of 3 and 8? 3 – 3, 6, 9, 12, 15, 18, 21, 24, 27, 30 8 – 8, 16, 24, 32, 40, 48, 56
Adding Fractions with Like Denominators When the denominators are the same, add the numerators and keep the denominator. Simplify if needed. 4 9 2 9 6 9 2 3 + = = 1 8 3 8 2 8 1 4 - + = - = -
Adding Fractions with UNLIKE Denominators When the denominators are different, you must create equivalent fractions with like denominators to add. Simplify if needed. 3 4 9 12 = 2 3 8 12 = + 5 12 17 12 = 1
Subtracting Fractions Subtracting Fractions with Like Denominators When the denominators are the same, subtract the numerators and keep the denominator. Simplify if needed. 7 9 _ 4 9 3 9 1 3 = = 5 8 _ 1 8 6 8 3 4 - = - = -
Subtracting Fractions Subtracting Fractions with UNLIKE Denominators When the denominators are different, you must create equivalent fractions with like denominators to subtract. Simplify if needed. 3 4 9 12 = _ 2 3 8 12 = 1 12
You Try It! Find each sum or difference.