There are slips of paper that are numbered from 1 to 15 in a hat. What is the theoretical probability that a slip of paper that is chosen will be an even number?

There are 15 slips of paper numbered from 1 to 15. The even numbers within this range are 2, 4, 6, 8, 10, 12, 14, totaling 7 even numbers. The theoretical probability of drawing an even number is the number of favorable outcomes (even numbers) divided by the total outcomes (total slips), which is ( \frac{7}{15} ).