What is the probability that if you roll a single standard die four times you will roll four different numbers?

5/18

It doesn't matter what number the first roll produces. The chance that the second throw will be the same is 1/6, so the chance of throwing one of the five different remaining numbers with the second dice is 5/6. Now there are only 4/6 ways of scoring with the third throw, and finally only 3/6 possibilities for the last throw.

So the probabiliy of throwing 4 different numbers = 1 * 5/6 * 4/6 * 3/6, w

hich is 5/6 * 2/3 * 1/2 = 5/18 = 0.2777777777777777or 27.77777777%

which is almost 28%