Find the height of this triangle.

An HP laser printer is advertised to print text documents at a speed of 18 ppm (pages per minute). The manufacturer tells you th

anastassius [24]

Answer:

0.288

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 normally distributed samples are solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore 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 pvalue, we get the probability that the value of the measure is greater than X.

Central Limit Theorem

The Central Limit Theorem estabilishes 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.

In this question, we have that:

$\mu = 17.48, \sigma = 3.25, n = 10, s = \frac{3.25}{\sqrt{10}} = 1.027740$

Find the probability that the mean printing speed of the sample is greater than 18.06 ppm.

This is 1 subtracted by the pvalue of Z when X = 18.06. So

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

By the Central Limit Theorem

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

$Z = \frac{18.06 - 17.48}{1.027740}$

$Z = 0.56$

$Z = 0.56$ has a pvalue of 0.712

1 - 0.712 = 0.288

The answer is 0.288

7 0

3 years ago

A study shows that 78% of the population of all calculus students consider calculus an exciting subject. Suppose 20 students ar

alexdok [17]

Answer:

0.046145 = 4.6145%

Step-by-step explanation:

We need to find the probability of 19 or 20 (all) students considering calculus to be an exciting subject, so first we find the probability for 19 students, then for 20 students, and we sum these probabilities.

The probability of the student NOT considering calculus to be an exciting subject is 1 - 0.78 = 0.22

For 19 students, we also have to calculate a combination of 20 choose 19, as these 19 students can be in different "position" among the 20 students, so:

C(20,19) = 20!/19! = 20

Probability of 19 students considering calculus to be an exciting subject:

C(20,19) * 0.78^19 * 0.22^1 = 0.039196756

Probability of 20 students considering calculus to be an exciting subject:

C(20,20) * 0.78^20 = 1 * 0.78^20 = 0.006948516

The final probability is:

0.039196756 + 0.006948516 = 0.046145272 = 4.6145272%

Rounding to six decimal places: 0.046145 = 4.6145%

5 0

3 years ago

As a salesperson, you are paid $50 per week plus $3 per sale. This week you want your pay to be at least $110. What is the minim

alexgriva [62]