Assume that when adults with smartphones are randomly​ selected, 46​% use them in meetings or classes. If 20 adult smartphone users are randomly​ selected, find the probability that exactly 15 of them use their smartphones in meetings or classes.

Assume that when adults with smartphones are randomly​ selected, 46​% use them in meetings or classes. If 20 adult smartphone users are randomly​ selected, find the probability that exactly 15 of them use their smartphones in meetings or classes.

Question
Probability
asked 2020-11-27
Assume that when adults with smartphones are randomly​ selected, 46​% use them in meetings or classes. If 20 adult smartphone users are randomly​ selected, find the probability that exactly 15 of them use their smartphones in meetings or classes.

Answers (1)

2020-11-28
Given:
\(\displaystyleμ={9.12}\)
ᵟ=Standard deviation=0.05
The z-score the value decreased by the mean, divided by the standard deviation.
\(\displaystyle{z}={\left(\frac{{{x}-μ}}{
0

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