Probability rolling dice

Question

Let's say you were to roll a dice 30 times. What is the number of times you would expect the number 2 to appear?

Answer 1

Assuming we are using a standard 6-sided die, then there are 6 possible outcomes when you roll the die once and only 1 of them is a two. So if you roll the die once, the probability of rolling a two is 1/6.

When we roll the die 30 times, we can expect about 1/6 of the 30 rolls to result in a two.

30•1/6 = 30/6 = 5.

We can expect to roll the number two about 5 times.