For the decimal, you are basically there, but it is going to be .3333333 and so on, so its never ending. For notation, you can write .33 and place a horizonatal line above the 3's. This signifies that you keep repeating the numbers under the line. If it was just 33%, it would be .33, but it says 33 1/3%, so it keeps repeating.
As for the fraction, 33/100, it is simplified as much as possible. 33 is factored as 1,33 3,11. So, none of those divide evenly, so its kind of a trick question in that it is already simplified. However, technically, it would be (33 1/3)/100, so, you need to do some work. Multiplying both top and bottom by 3 makes 33 1/3 into 100, and 100 into 300.
So, now you have 100/300 which I am sure you can agree will simplify down to 1/3.
