To express the multiplication of 5 and 13 as a fraction, we need to first calculate the product. When we multiply 5 by 13, we get 65. Now, to express this as a fraction, we can write it as:
65/1
This is because any whole number can be expressed as a fraction by placing it over 1. So, 5 x 13 can be represented as 65/1, which is a valid fraction.