Well, first make the whole number a fraction with the same denominator as the improper fraction.
Then you can simply add the former whole number with the improper fraction.
Here is an example:
We have the whole number 2 and the improper fraction 4/3.
The whole number has the have the denominator 3.
So... 2*3/3 + 4/3.
= 6/3 +4/3
= 10/3
So 10/3 is the answer.
Always remember that even though you make the whole number into a fraction, if you simplify it, it will always be equal to the former whole number. In my example, 6/3 can be simplified to 2.