Either an odd number or an even prime number.
Well, the only even prime number is 2. Everything else is divisible by 2, making it not prime.
So, we know on a 16 sided die that the numbers 1, 3, 5, 7, 9, 11, 13, and 15 are on there and apply to the odd number portion.
We have 8 numbers plus 1 extra number. 9 numbers in total, so divide 9 by 16.
9/16 = 0.5625
Rounded to the thousandths, it's 0.563.
Now, in this, we are NOT going to look at the Freshman, Sophomore, or Junior sections, as it is given that they are a Senior.
Our denominator will be 16+15+7, which is 38
Now we take however many preferred evening classes (7) and divide that by 38
7/38 = 0.1842105263157895
Rounded to the nearest thousandth, the answer is 0.184.