Add & subtract, unlike fractions. These grade 7 worksheets provide practice in adding and subtracting fractions with both like and unlike denominators.
2. Adding / Subtracting Fractions What are Equivalent Fractions? Fractions that have the same value. For example, 1/2 = 2/4 = 3/6 EQUIVALENT means EQUAL so all equivalent fractions have to be equal. I have a pizza and cut in half. I give half to my friend, and I keep half. I take the half I have and cut it in half again. I still have half of the pizza.
3. Adding / Subtracting Fractions How do you make an equivalent fraction? MULTIPLY or DIVIDE a fraction by another fraction that is equal to one. In other words, MULTIPLY or DIVIDE the numerator and denominator by the same number ! For example:
4. Adding / Subtracting Fractions RULE: You CANNOT add or subtract fractions unless the denominators are the same. NEVER add or subtract the denominators!
5. Adding / Subtracting Fractions Steps for Adding/Subtracting Fractions with Uncommon Denominators
6. Adding / Subtracting Fractions STEP 1: ½+¼ You can multiply 2 and 4 to get 8, Find a common which is a common denominator. Or denominator. you can list the multiples of 2 and 4 You can either multiply until you find the LCM. the denominators OR 2 – 2, 4, 6, . . . find the LCM by listing 4 – 4, 8, 12 . . . all the multiples of both numbers. The LCM is 4.
7. Adding / Subtracting Fractions STEP 2: Write equivalent • ½ = 4/8 fractions with the • ¼ = 2/8 common denominator.
8. Adding / Subtracting Fractions STEP 3: Write the problem ½+¼ with equivalent 4/8 + 2/8 = 6/8 fractions.
9. Adding / Subtracting Fractions STEP 4: You can simplify Simplify if needed. Don’t forget when 6/8 to 3/4 simplifying, divide Because the GCF both the of 6 and 8 is 2, so numerator and 6 divided by 2 is 3 denominator by and 8 divided by 2 the GCF. is 4.