The answer to Probability theory
It is found that when a particular 4-sided die is rolled a 1 occurs 22.8% of the time, a 2 occurs 25.3% of the time, a 3 occurs 20.8% of the time, and a 4 occurs 31.1% of the time.
a) If the die is rolled six times, what is the probability that an odd number occurs exactly three times?
b) What is the expected value of a single roll of the die?