4/3
An easy way to think about this is by breaking 1.33 into 2 parts.
First start by taking away the whole number.
Now find the corresponding decimal to fraction. I know 0.33=1/3
Next take 1/3 and add the second factor you had which was the whole number.
1/3+1=4/3. I know this because 3/3=1 so 3/3+1/3=4/3
0.333333=1/3 so if i take 1/3+1=4/3.