Math Math Math!
Simple, straightforward math help!
Simplifying a fraction just means that we're going to reduce the numerator & denominator by the same amount to simplify the look of the fraction.
You can do it by working out the largest number which divides into BOTH the numerator (the top number) and the denominator (the bottom number) ...
We first work out a number which divides into both 10 & 16. Lets start with 10 - that does divide into the numerator (10) but doesn't divide into the denominator (16), so that doesn't work. The same goes for the numbers 9, 8, 7, & 6. But 5 does divide into 10 - as 10 divided by 5 is 2. But, 5 doesn't divide into 16. So, we then try 4 - this doesn't divide into 10 but it does divide into 16 - so 4 is no use to us either. How about 3? Well, this doesn't divide into 10 or 16 either. Finally, we come to 2 - this does divide into both 10 & 16 - so we can use this - we divide both 10 & 16 by 2 and we get ...
The other way you can do this is by dividing the numerator & denominator by the same small number, say 2 or 3 and then repeating this process until you can do it no longer ...
Do it whichever way you're most comfortable with - but always remember to divide the numerator and denominator by the SAME number every time!