TenMarks teaches you how to subtract fraction with like denominators.
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Learn about Subtraction of Like Fractions Let’s learn about subtraction of like fractions. We’re given two problems. I’m going to do them one by one. The first one wants us to subtract 1/16-5/16. 1/16-5/16. Now, since the denominators are the same, if the denominators are equal, it’s a like fraction. Denominators are equal which means it is a like fraction set or the fractions are alike. So how do we do this? If we want to take away, 5/16 from 1/16, if the denominators are the same, we copy the denominator and we subtract the numerators, so we get 1-5. 1-5 is -4/16. I can divide the numerator and denominator by their GCF which is 4. 4/4 is -1 and 16÷4 is 4, so the answer is -1/4. In the second problem, let’s change the color of my pen. We’ll try something a little different. We are trying to take -1/16 and add to it 5/16. These are like fractions of course because the denominators are the same but the key thing to remember is since the signs are different, it’s a subtraction operation. If the signs are different, it is essentially a subtraction operation. Let’s see how. If we perform this: -1/16+5/16. Since the denominators are the same, I copied the denominators down. The numerators become -1+5 which is the same as 5-1. -1+5 is the same as 5-1. 5-1 is 4 and 16 gets copied or -1+5 would have resulted in 4, it’s one and the same thing. I can divide both the numerator and denominator by their GCF to get ¼ which is the answer in the simplest form. Key thing to remember is if the signs are different, it’s a subtraction operation. Now, -1+5 is the same as 5-1. It’s one and the same thing. The result is 4/16 which in simplest form is ¼.