Final answer:
The random variable X represents the number of days Ellen practices music in a week and it can take on the values 0, 1, 2, and 3, which means the correct answer is option a. X = {0, 1, 2, 3}.
Step-by-step explanation:
The values that the random variable X can take on are based on the frequency of Ellen's music practice days within a week. Based on the information given, X represents the number of days Ellen practices music in a week. Here are the possible values of X:
- 3 days: Ellen practices music three days a week 85% of the time.
- 2 days: She practices for two days 8% of the time.
- 1 day: She practices for one day 4% of the time.
- 0 days: She does not practice any days 3% of the time.
Therefore, the random variable X can take on the values 0, 1, 2, and 3, which corresponds to option a. X = {0, 1, 2, 3}.