Use a normal approximation to find the probability of the indicated number of voters. In this​ case, assume that 134 eligible voters aged​ 18-24 are randomly selected. Suppose a previous study showed that among eligible voters aged​ 18-24, 22% of them voted. What is the probabilty that fewer than 32 of 134 eligible voters voted?

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Answer:

The Required Probability is 0.8525

Step-by-step explanation:

Given:

Number of people, n = 134

Proportion of people voted , p = 22% = 0.22

To find: the Probability that fewer than 32 of 134 eligible voters voted.

First we find the mean and Standard deviation,

Means,

[tex]\mu=n\times p=134\times0.22=29.48[/tex]

Standard Deviation,

[tex]\sigma=\sqrt{n\times p\times q}=\sqrt{134\times0.22\times0.78}=\sqrt{22.9944}=4.795[/tex]

Now the Probability,

[tex]P(X<32)=P(X\leq34.5)=P(\frac{X-\mu}{\sigma}\leq\frac{34.5-29.48}{4.795})=P(z\leq1.047)=0.8525\::(using\,z-score\:table)[/tex]  

Therefore, The Required Probability is 0.8525

The distribution of apple follows a normal distribution.

The probability that  fewer than 32 of 134 eligible voters voted is 0.70

The given parameters are:

[tex]p =22\%[/tex] --- proportion of those that voted

[tex]n = 134[/tex] --- standard deviation

[tex]x = 32[/tex]

First, we calculate the mean

[tex]\mu = np[/tex]

So, we have:

[tex]\mu = 134 \times 22\%[/tex]

[tex]\mu = 29.48[/tex]

Next, calculate the standard deviation

[tex]\sigma = \sqrt{\mu \times (1 - p)}[/tex]

So, we have:

[tex]\sigma = \sqrt{29.48 \times (1 - 22\%)}[/tex]

[tex]\sigma = 4.80[/tex]

Next, we calculate the z score

[tex]z = \frac{x - \mu}{\sigma}[/tex]

Substitute known values

[tex]z = \frac{32 - 29.48}{4.80}[/tex]

[tex]z = \frac{2.52}{4.80}[/tex]

[tex]z = 0.525[/tex]

So, the probability that fewer than 32 voted is:

[tex]P(X<x) = P(Z<z)[/tex]

This gives

[tex]P(X<32) = P(Z<0.525)[/tex]

From z-score table, we have:

[tex]P(z>0.525) = 0.70021[/tex]

This means that:

[tex]P(x<32) =0.70021[/tex]

Approximate

[tex]P(x<32) =0.70[/tex]

Hence,  the probability that  fewer than 32 of 134 eligible voters voted is 0.70

Read more about probabilities of normal distributions at:

https://brainly.com/question/6476990