Question

Ellen has music practice each week.

She practices for three days 82 percent of the time, two days 8 percent of the time, one day 4 percent of the time, and no days 3 percent of the time.

One week is selected at random.





Part A

Use the drop-down menu to complete the sentence.



The discrete random variable X can be defined as


(b)
Part B

Use the given information to complete the table.



x
P(x)
0

1

2

3 .82

Answer 1

Part A
X = the number of days Ellen practices in a randomly selected week.

Part B
x = 0 → P(x) = 0.03
x = 1 → P(x) = 0.04
x = 2 → P(x) = 0.08
x = 3 → P(x) = 0.82

(Note: these come from 3%, 4%, 8%, 82% as given; they sum to 0.97, so check the original percentages if the total must be 1.)