If you understand most of it i'll just give simple answer. For it to make sense you need the bottom number to match the others bottom number. Like 3/7 and 1/14 would be 6/14 and 1 1/14 Then to find the difference you'd just minus the two top numbers. To make the bottom numbers the same is you need to find a common number for them. 2/15 and 1/2, you know 1/2 is 50%. But 2/15 can not be split. So you make 2/15 into 4/30 and 1/2 into 15/30. The question is what can be added to make it greater than 15/30. That would be anything 12/30 or 6/15 and up. Mixed fractions are a little different. You take the whole number and multiply it by bottom number then add the top number, like: 2 7/9 and 1 1/3 would be 25/9 and 4/3. Now you should find same bottom number, so it'd be: 25/9 and 12/9. That is correct because 3 goes into nine 3 times, then you multiply the top number 3 times. But for you to answer this ''less than 1" It'd be 1 2/9 and 1 1/9 because the difference is 1/9 and that's less than 1 which 1 in whole number form would be 9/9. It's hard for me to explain things, so if you don't understand something please ask me.
