A numertator is the top number and the denominators are the bottom number of a fraction. You can tell the difference because if you look at the top number of one fraction and you look at the other that you're supposed to compare and there the same number, then they are the same. For example, 1/2 and 1/3 have the same numetators but not denominators. Now for denominators you have to look at the bottom number but if the two fractions you're comparing have the same bottom number then there the same, but if they have two different bottom numbers, then they are not the same. For example again: 1/3 and 1/9 The may seem the same but there not since the bottom number is different.
2 fractions with the numerator and different denominators can be compared when you find the lowest common denominators (LCD. For example 1/2 and 1/3 have the same numerator, but the denominators are not so you have to find the LCD. The LCD, in this case, is 6, so the fractions would be 3/6 and 2/6 and now if you compare you can tell that 3/6 is greater than 2/6 so 1/2 is greater than 1/3.
