Adding Mixed Numbers TeacherTwins©2015
Warm Up Add or subtract. 𝟐 𝟕 + 𝟒 𝟕 2. 𝟑 𝟓 + 𝟐 𝟑 𝟔 𝟕 1 𝟒 𝟏𝟓 𝟐 𝟕 + 𝟒 𝟕 2. 𝟑 𝟓 + 𝟐 𝟑 3. 𝟒 𝟓 - 𝟏 𝟏𝟎 4. 𝟔 𝟕 - 𝟐 𝟗 𝟔 𝟕 1 𝟒 𝟏𝟓 𝟕 𝟏𝟎 𝟒𝟎 𝟔𝟑
Example 1: Add 12 𝟑 𝟒 + 3 𝟏 𝟐 Get a common denominator for the fractions. The LCD is 4. 12 𝟑 𝟒 = 12 𝟑 𝟒 + 3 𝟏 𝟐 x 2 = 3 𝟐 𝟒 Add the whole numbers and fractions. x 2 15 𝟓 𝟒 Make 𝟓 𝟒 a mixed number. 15 + 1 𝟏 𝟒 = 16 𝟏 𝟒 𝟓 𝟒 = 1 1 4
Example 2: Add 3 𝟓 𝟔 + 5 𝟏𝟏 𝟏𝟐 3 𝟓 𝟔 = 3 𝟏𝟎 𝟏𝟐 𝟐𝟏 𝟏𝟐 = 1 𝟑 𝟒 + 5 𝟏𝟏 𝟏𝟐 = 5 𝟏𝟏 𝟏𝟐 8 𝟐𝟏 𝟏𝟐 = 8 + 1 𝟑 𝟒 = 9 𝟑 𝟒
Example 3: Suppose a shark travels 25 𝟏 𝟐 miles in one hour and he travels 24 𝟒 𝟓 miles the next hour. How far did the shark travel during the two hours? 25 𝟏 𝟐 +𝟐𝟒 𝟒 𝟓 = 50 𝟑 𝟏𝟎
Practice Add. 2 𝟏 𝟑 + 6 𝟑 𝟒 12 𝟒 𝟕 + 15 𝟑 𝟓 9 𝟏 𝟏𝟐 2𝟖 𝟔 𝟑𝟓
Closure Think of a problem where you add mixed numbers but the answer is not a mixed number. Answers vary. Fractions need to add to a whole number.