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Chapter 4: Q. 109 (page 296)

Ellen has music practice three days a week. She practices for all of the three days 85% of the time, two days 8% of the time, one day 4% of the time, and no days 3% of the time. One week is selected at random. What values does X take on?

Short Answer

Expert verified

X takes on the values as0,1,2,3

Step by step solution

01

Content Introduction

Random variable is defined as variables whose values are unknown and we are supposed to find it.

02

Content Explanation

We are given,

Through a stem diagram, we can say that she practices three days, two days, one day, and no days Therefore the values of X will be 0,1,2,3. It also tells us the probability of each of these events. The probability is represented as 3% of the time she practices on zero day, she practices one day, 4% of time, then she practices two days 8% of the time etc.

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