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Adding, subtracting, multiplying, and dividing fractions. Amie Schneider Teacher page. Adding Fractions-. Step 1- Make sure both the fractions have a common denominator. Example- 1/3 + 1/6 = ? ^Not the same^ Find a common denominator Multiply 1/3 by 2 on the top and bottom
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Adding, subtracting, multiplying, and dividing fractions Amie Schneider Teacher page
Adding Fractions- • Step 1- • Make sure both the fractions have a common denominator. • Example- 1/3 + 1/6 = ? • ^Not the same^ • Find a common denominator • Multiply 1/3 by 2 on the top and bottom • (2)(1) = 2 (2)(3) = 6 • New fraction = 2/6
Adding Fractions- • Step 2- • Now having common denominators we can add the fractions • Only add the numerators (top) • 2/6 + 1/6 = • 2 + 1 = 3 • Denominator remains 6 • Answer 3/6
Adding Fractions- • Step 3- • If possible simplify your answer • Does 3/6 equal something else? • Find the greatest common factor • 3/6 = 1/2 because the GCF was 3 • 3 ÷ 3 = 1 and 6 ÷ 3 = 2 =
Subtracting Fractions- • Step 1- • Make sure the denominator are the same • Example- 1/2 - 1/10 = ? • ^Not the same^ • Find a common denominator • Multiply 1/2 by 5 • (1)(5) = 5 (2)(5) = 10 • New fraction = 5/10
Subtracting Fractions- • Step 2- • Now that we have common denominators we can subtract! • Only subtract the numerators. • Example- 5/10 – 1/10 = ? • 5 – 1 = 4 • Denominator remains 10 • Answer – 4/10
Subtracting Fractions- • Step 3- • If possible simplify your answer. • Does 4/10 equal something else? • Find the greatest common factor • 4/10 = 2/5 because the GCF is 2 • 4 ÷ 2 = 2 and 10 ÷ 2 = 5
Multiplying Fractions- • Step 1- • Multiply the numerators • Example- 1/2 x 2/5 = ? • 1 x 2 = 2 *This time we don’t need a common denominator!
Multiplying Fractions- • Step 2- • Multiply the denominators • Example- 1/2 x 2/5 = ? • 2 x 5 = 10
Multiplying Fractions- • Step 3- • If possible simplify your answer • Answer – 2/10 • Find the greatest common factor • 2/10 = 1/5 because the GCF is 2 • 2 ÷ 2 = 1 and 10 ÷ 2 = 5
Dividing Fractions- • Step 1- • “Skip, Change, Flip” • Don’t change the first fraction – Skip • Change the ÷ to a x- Change • Flip the second fraction upside down (the reciprocal)- Flip • Example- 1/3 ÷ 2/4 becomes 1/3 x 4/2
Dividing Fractions- • Step 2- • Multiply the numerators • 1 x 4 = 4 • Multiply the denominators • 3 x 2 = 6 • Answer- 4/6
Dividing Fractions- • Step 3- • If possible simplify your answer • Find greatest common factor • Answer- 4/6 • 4/6 = 2/3 because the GCF is 2 • 4 ÷ 2 = 2 and 6 ÷ 2 = 3
#1-What is 2/5 + 1/5? • 3/5 • 3/10 • 2/25 • 1/5
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#2-What is 3/4 - 4/6 ? • 7/10 • 1/12 • 12/24 • 1/2
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#3-What is 1/2 x 2/3? • 3/5 • 1/6 • 1/3 • 2/5
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#4-What is 1/4 + 2/3? • 11/12 • 3/7 • 2/12 • 3/12
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#5- What is 1/3 ÷ 2/3? • 1/3 • 2/6 • 1/2 • 2/3
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#6- What is 2/5 – 1/3? • 2/15 • 1/15 • 3/8 • 1/2
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#7- What is 3/4 x 1/8? • 3/32 • 2/4 • 4/12 • 3/12
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#8- What is 1/8 ÷ 2/3? • 2/24 • 2/16 • 3/16 • 1/5
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