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In Exercises 21鈥24, assume that when adults with smartphones are randomly selected, 54% use them in meetings or classes (based on data from an LG Smartphone survey).

If 8 adult smartphone users are randomly selected, find the probability that exactly 6 of them use their smartphones in meetings or classes.

Short Answer

Expert verified

The probability of selecting exactly six out of eight smartphone users who use their smartphones in meetings or classes is equal to 0.147.

Step by step solution

01

Given information

A group of eight adult smartphone users was selected. The probability of selecting a user who uses his/her smartphone in meetings or classes is equal to 0.54.

02

Required probability

Let X denote the users who use their smartphones in meetings or classes.

Let success be defined as selecting a user who uses his/her smartphone in meetings or classes.

The number of trials (n) is given to be equal to eight.

The probability of success is calculated below:

p=54%=54100=0.54

The probability of failure is calculated below:

q=1-p=1-0.54=0.46

The number of successes required in eight trials should be equal to x=6.

The binomial probability formula is as follows:

PX=x=nCxpxqn-x

By using the binomial probability formula, the probability of getting six users who use their smartphones in meetings or classes is computed below:

PX=6=8C60.5460.468-6=8!6!8-6!0.5460.462=0.14690.147

Therefore, the probability of getting six users who use their smartphones in meetings or classes is equal to 0.147.

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