How to Solve Addition & Subtraction for Mixed Fractions

By Charlie Kasov

Solving addition and subtraction for mixed fractions will require you to work with improper fractions. Solve addition and subtraction for mixed fractions with help from a high school math tutor in this free video clip.

Transcript

Hi, I'm Charlie Kasov, and this is "how to solve addition and subtraction for mixed fractions." Now, addition and subtraction for mixed fractions is easy, if you remember two steps. The first, turn them into improper fractions. The second, find the lowest common denominator. So, let's say we have one and three fifths, and we have one and one fourth. So, if we have these two, if we wanna add them or subtract them, the first thing we have to do is turn them into improper fractions, and that means making it a big, top heavy fraction. So, one is like five fifths, plus three fifths, which becomes eight over five. So, one and three fifths is the same as eight over five. One and one fourth is four over four, plus one over four, which is five over four. And, then, now we have to find the lowest common denominator, and the LCD of five and four is 20. So, to get to 20, we have to multiply by four over four, over here, and four times eight is 32, over 20, and five over four, we have to multiply by five over five, and that's to get the denominator to 20. So, we get 25 over 20. So, now, we can either add or subtract as we like. And, if we add, we get 57, and if we subtract, we get seven. So, I'm Charlie Kasov, and that's how you add and subtract mixed fractions.

About the Author

Charlie Kasov has been tutoring high school mathematics since 2004. He is qualified to teach several math subjects, including geometry, algebra, trigonometry and probability.