If I roll 5 standard 6-sided dice and multiply the number on the face of each die, what is the probability that the result is a composite number?
Well, what is the definition of a composite number. It is a number that has AT LEAST one factor other than itself and 1 !!!! So, if you throw 5 dice, you are necessarily going to MULTIPLY 5 numbers by each other, hence you will, of course, have a composite number !!! Example: 23415. 2 x 3 x 4 x 1 x 5=120. Now, if you throw 5 ones, 11111, you will have 1, which is still considered composite, since it certainly is NOt a prime number.
So, your probability is 100%.
Now if you were to add them up instead of multiplying them, then that is a different matter!! Then you would have: 2,466 primes / 6^5 =137 / 432