Well, you didn't provide any examples that you needed so I will attempt to help with my own examples.
To simplify a fraction, you need to find a number both the numerator and denominator can be simplified by. For example:
4/12 - you can use either four or two, we're gonna use four
1/3 would be your simplified form.
For mixed numbers, like 1 and 5/35 for instance, would be simplified in a similar instance. Divide both by 5 and get the simplified form of 1 and 1/7.
For improper fractions, such as 49/7, you can simplify them the same way as well. The final result would b 7. However, if you'd like one that isn't a perfect square like 32/12 then, yet again, you'd find a common number to divide which could be 4. Then the simplified version would be 4/3. However, if it was meant to be transformed into a mixed number than you'd get 2 and 8/12 which would further be simplified to 2 and 2/3.
Hope this helps!