Mathematics, 23.06.2021 04:40 Faber9714

from first-time customers. A random sample of 161 orders will be used to estimate the proportion of first-time-customers. What is the probability that the sample proportion is between 0.35 and 0.45

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This probability that the sample proportion is between 0.35 and 0.45 is the p-value of $Z = \frac{0.45 - \mu}{\sqrt{\frac{p(1-p)}{160}}}$ subtracted by the p-value of $Z = \frac{0.35 - \mu}{\sqrt{\frac{p(1-p)}{160}}}$ . These p-values are found looking at the z-table.

Step-by-step explanation:

To solve this question, we need to understand the normal probability distribution and the central limit theorem.

Normal Probability Distribution:

Problems of normal distributions can be solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the z-score of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.

Central Limit Theorem

The Central Limit Theorem establishes that, for a normally distributed random variable X, with mean $\mu$ and standard deviation $\sigma$ , the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean $\mu$ and standard deviation $s = \frac{\sigma}{\sqrt{n}}$ .

For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.

For a proportion p in a sample of size n, the sampling distribution of the sample proportion will be approximately normal with mean $\mu = p$ and standard deviation $s = \sqrt{\frac{p(1-p)}{n}}$

Estimate of the proportion:

This is p, and thus, we use $\mu = p$ .

Sample of 160

This means that:

$n = 160, s = \sqrt{\frac{p(1-p)}{160}}$

What is the probability that the sample proportion is between 0.35 and 0.45?

Answer from: Quest

step-by-step explanation:

your mom

Which one of these triangle pairs can be mapped to each other using a single refelection

Answer from: Quest

1 x=22.52

2: 65/39=604+39x

65x-39x=604

26x=604

x=604/26

×=23.23

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