Adding and Subtracting Fractions

This is a Study sheet to help you practise and review

Adding Fractions

1/2 + 3/4= 4/4 or 1 hole i got this answer by multiplying 2 by it self and that gave me 4 so i know my denomarater is 4 than i add the numraters
How to Add Fractions
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adding improper fractions

10/5 + 2/5= 2 2/5 i got this by doing this starting off my denomanator is 5 and my numaraters are 10 and 2 what i need to do with 10/5 is see how many times 5 can go into 10 and in this case its twice so i already know 5 goes into 10 twice so ill put a 2 in front of the fraction and with 2/5 i add the 2 so that is how i got 2 2/5
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Subtracting Fractions

Subtracting Basic Fractions

Equation: 2/5 - 3/10


Explanation:

To do this equation start by finding a common denominator to do that you can list the multiples or multiply the two denominator and the common denominator would be 10. Now whatever you did to each denominator to get 10 do that to the numerators as well. So in the first fraction you need to do 5 x 2 to get 10 so now you have to multiply the numerator with two as well, 2 x 2=4. Since in the second fraction the denominator is already at 10 you don't need to do anything to it, but if it wasn't you would multiply the numerator with whatever you multiplied the denominator with. So now the equation is 4/10 - 3/10. Now subtract the numerators but keep the denominator the same. So 4-3=1 and the final answer is 1/10


Steps:

1. Find the common denominator preferably the lowest common denominator

2. Whatever you did to the denominators of each fraction to get the common denominator do to the numerators as well

3. Subtract the numerators, and keep the denominators the same

4. Simplify if needed


Numbers:

2/5 - 3/10 ~equation

= 4/10 - 3/10 ~common denominators

=1/10 ~numerators subtracted, final answer

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The subtracting part starts at 2:40

Math Antics - Adding and Subtracting Fractions

Subtracting Improper fractions

Equation: 4/2 - 4/3


Explanation:

To do this equation start by finding the common denominator to do that you can list the multiples of the denominators until you find a common one or you can multiply the denominators together. In this case the common denominator is 6. Next whatever you did to the denominator of each fraction, do to the numerator as well. So since I had to multiply the denominator of the first fraction by 3 I need to multiply the numerator with 3 as well, 4 x 3=12. Now do that to the other fraction too. So to get six I need to multiply the second denominator by 2, so I have to multiply the numerator with 2 as well, 4 x 2=8. Now the fractions are 12/6 - 8/6. The next step is to subtract the numerators as normal, and keep the denominators the same. So 12-8=4 so the answer would be 4/6. You can still go further by simplifying the fraction so 4/6=2/3. If by the end the fraction is still improper you should turn it back into a mixed number. To do that you need to ask yourself how many times the denominator goes into the numerator, the number of times that is, is the whole number. The leftover is the numerator and the denominator stays the same


Steps:

1. Find the common denominator

2. Whatever you did to the denominator do to the numerator as well

3. subtract the numerators

4. if still improper convert to a mixed number

5. Simplify if needed


Numbers:

4/2 - 4/3

= 12/6 - 8/6 ~common denominator

= 4/6 ~subtracted denominator

= 2/3 ~simplified

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Different ways to find common denominators

I couldn't find a video for subtracting improper fractions so when he says the adding improper example just think of it as a subtraction equation starts at 3:20
Adding and Subtracting Mixed Numbers and Improper Fractions

Subtracting mixed fractions

Equation= 3 2/3 - 1 2/5


Explanation:

To subtract mixed numbers start by turning the mixed numbers into improper fractions. To do that you need to multiply the whole number by the denominator then add the numerator. So for the first fraction the improper fraction would be 3 x 3+2=11 and for the second fraction the improper fraction would be 1 x 5+2=7. You would keep the denominator the same. So the equation is 11/3 - 7/5. Next I'm going to find the common denominator to do that I am going to multiply the two denominators which give me 15. Now whatever I needed to do to each fraction's denominator to get 15 do that to the numerator as well. For the first fraction I need to multiply the denominator by 5 so I have to multiply the numerator as well, 11 x 5=55. Now do that to the other fraction as well so 5 x 3=15, the numerator 7 x 3= 21. So the fractions are 55/15 and 21/15. Now subtract the numerators 55-21=34 and the denominator stays the same so the answer is 34/15. But since the equation is in mixed numbers the answer should be in mixed numbers too. So to convert the improper fraction I need to ask myself how many times the denominator goes into the numerator, 15 goes into 34 two times. So the whole number is two the leftover is the numerator and the denominator stays the same. So the answer is 2 4/15. If you can reduce it then simplify it


Steps:

1. Convert mixed numbers to improper fractions

2. Find a common denominator (look above for the different ways to find the common denominator)

3. whatever you did to the denominator of each fraction do to the numerator as well

4. Subtract the numerators

5. Turn improper fraction back into mixed (# of times denominator goes into numerator leftover in the numerator and denominator stays the same)

6. Simplify if needed


Numbers:

3 2/3 - 1 2/5 ~equation

=11/3 - 7/5 ~improper to mixed

=55/15 - 21/15 ~common denominator

= 34/15 ~numerators subtracted

= 2 4/15 ~mixed number final answer

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How to Add or Subtract Mixed Numbers

Hope this helped you study, review or learn more :)