Lesson 4 Add and Subtract Unlike Fractions

Lesson 4: Add and Subtract Unlike Fractions Objective: Swbat add or subtract unlike fractions. Do Now: 1. 5 + 3 2. 7 - 5 12 12 11 11 3. 7 - 3 4. 11 + ( -5 ) 5. -2 – ( -5 ) 8 8 16 16 3 3

Lesson 4: Add and Subtract Unlike Fractions Definition Unlike fractions are fractions with different denominators.

Lesson 4: Add and Subtract Unlike Fractions The table shows the fractions of one hour for certain min. Number Min. Fraction of Hour Simplified Fraction 5 5/60 10 10/60 15 15/60 20 20/60 30 30/60 1.) What fraction of one hour is equal to the sum of 15 minutes and 20 minutes 2.) Write each fraction of an hour in simplified form. 3.) Explain why 1/6 hour + 1/3 = ½ hour.

Lesson 4: Add and Subtract Unlike Fractions Add or Subtract Unlike Fractions with different denominators: Rename the fractions using the least common denominator (LCD) Add or Subtract as with like fractions Simplify the sum or difference

Lesson 4: Add and Subtract Unlike Fractions Example 1: 1 + 1 2 4 1 x 2 2 x 2 2 + 1 = 3 4 4 4

Lesson 4: Add and Subtract Unlike Fractions Example 2: -2 – 1 3 2 -2 x 2 1 x 3 LCD is 6 3 x 2 2 x 3 -4 – 3 = -4 – 3 = -7 6 6 6 6 = -1 1 6

Lesson 4: Add and Subtract Unlike Fractions Try It 1 2 + 1 4 = 1 6 + 2 3 = 1 4 + 3 8 =

Lesson 4: Add and Subtract Unlike Fractions 1.) ( −3 4 + 5 9 ) + 7 4 = 2.) 2 5 + ( 4 7 + 3 5 ) =

Lesson 4: Add and Subtract Unlike Fractions 3.) ( −3 10 + 5 8 ) + 23 10 = 4.) −2 3 - 1 2 = 5.) 5 8 - 1 4 =

ClassWork Guided Practice #1-8 Independent Practice #1-12 Problem Solving #1 - 6

Closure Question: How can you find the LCD when you have unlike fractions? Exit Ticket: Homework: Practice Worksheet #1 - 16

Exit Ticket -3 + 2 8 5

Homework