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Chapter 4: Q.10 (page 282)

Define the random variable X.

Short Answer

Expert verified

Xbe the number of days in a week that Ellen has music training.

Step by step solution

01

Given Information

Ellen has music practice three days a week, all three days are chosen at random85 percent of the time, two days are chosen at random 8 percent of the time, one day is chosen at random 4 percent of the time, and no days are chosen at random 3percent of the time.

02

Concept Used

A random variable depicts the problem's features, and we'll call X the number of days Ellen has music training in a week.

According to discrete distribution properties,

The probability mass function of a discrete variableX is known asP(X).

i. P(X)≥0for all X

ii.∑P(X)=1

03

Explanation & conclusion

As a result, letXrepresent the number of days Ellen performs music in a week.

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Most popular questions from this chapter

A consumer looking to buy a used red Miata car will call dealerships until she finds a dealership that carries the car. She estimates the probability that any independent dealership will have the car will be 28%. We are interested in the number of dealerships she must call.

a. In words, define the random variable X.

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Complete Table 4.28 using the data provided.

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