When you are comparing fractions you are trying to see the difference in then, by the amount.for example if you had 4/5 and 3/4 you have to find a common denominator to see which one is bigger. The common denominator would be 20. You multiply the numerator by 5 and then the denominator by 5. The fractions you should get are 16/20 and 15/20. Now take a look at them and see which one is bigger. 16/20 is bigger and reduced is 4/5. So 4/5 is you biggest fraction out of these 2.
When ordering fractions it is very simple, these are the fractions:
3/4, 4/5, 1/2 from least to greatest.
Find a common denominator and then multiply the denominator and the numerator by a number to get to the common denominator, like this:
3/4, 4/5, 1/2 20- common denominator
3/4 x 5 = 15/20
4/5 x 4 = 16/20
1/2 x 10 = 10/20
Now put them in order from least to greatest or greatest to least, whatever the instructions tell you to do.
10/20, 15/20, 16/20
Remember to put them back to their original fraction.
1/2, 3/4, 4/5