Well 13/4 simplified would be 3.25 if you divide 13 by four. Or you can use a simpler way just see how many times four can go into 13 which is three so three is you whole number, then you find out how much is left over which is one there for that will be your fraction. Since one is your numerator and four should be the denominator the answer to this question would be 3 1/4