Adding+and+Subtracting+Fractions

-Addition 3/5+1/5=4/5 First I looked at 3/5, and then I looked at 1/5. Next, I looked at the denominators. They are both five, so I look at the numerators. They are three and one. I just added them together and got four. Last I took four and put it over five like this: 4/5. And that is the answer.

But what if the denominator is different? Well you just look at the denominator and find the least common multiple, or LCM. The LCM is what you get when you when you times one denominator by 1,2,3,4,5,6,...exc, and do the same thing with the other denominator. The first number that matches is the LCM.

2/3+3/4=5/12 First I looked at the problem and saw that the denominators were different, so i found the LCM. It was 12, so I looked at the numerator and they are 2 and 3. I just added them together and got 5. So that's my answer. 5/12.

-Subtraction 4/6-1/6=3/6 First, I looked at 4/6, and 1/6. Next, i saw that the denominators were the same so I left them alone. Then I looked at the numerators, and they were 4 and 1. I got 3. So my answer is 3/6.

2/3-3/5=5/15 Once again, what if the denominators are different? Well, it's pretty much the same as addition only you subtract. You just find the LCM. In this case, the LCM is 15. Here is an easier way to write the problem so you don't get so confused.