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sertanlavr [38]

3 years ago

8

The weight of a small Starbucks coffee is a normally distributed random variable with a mean of 330 grams and a standard deviati

on of 12 grams. Find the weight that corresponds to each event. (Use Excel or Appendix C to calculate the z-value. Round your final answers to 2 decimal places.) a. Highest 20 percent

1 answer:

just olya [345]3 years ago

3 0

Answer:

Weights of at least 340.1 are in the highest 20%.

Step-by-step explanation:

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.

In this problem, we have that:

$\mu = 330, \sigma = 12$

a. Highest 20 percent

At least X

100-20 = 80

So X is the 80th percentile, which is X when Z has a pvalue of 0.8. So X when Z = 0.842.

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

$0.842 = \frac{X - 330}{12}$

$X - 330 = 12*0.842$

$X = 340.1$

Weights of at least 340.1 are in the highest 20%.

You might be interested in

A tattoo enthusiast website claims that :

KATRIN_1 [288]

Answer:

The probability that a person is a Millennial given that they have tattoos is 0.5069 (50.69%) or about 0.51 (51%).

Step-by-step explanation:

We have here a case where we need to use Bayes' Theorem and all conditional probabilities related. Roughly speaking, a conditional probability is a kind of probability where an event determines the occurrence of another event. Mathematically:

$\\ P(A|B) = \frac{P(A \cap B)}{P(B)}$

In the case of the Bayes' Theorem, we have also a conditional probability where one event is the sum of different probabilities.

We have a series of different probabilities that we have to distinguish one from the others:

The probability that a person has a tattoo assuming that is a Millennial is:

$\\ P(T|M) = 0.47$

The probability that a person has a tattoo assuming that is of Generation X is:

$\\ P(T|X) = 0.36$

The probability that a person has a tattoo assuming that is of Boomers is:

$\\ P(T|B) = 0.13$

The probability of being of Millennials is:

$\\ P(M) = 0.22$

The probability of being of Generation X is:

$\\ P(X) = 0.20$

The probability of being of Boomers is:

$\\ P(B) = 0.22$

Therefore, the probability of the event of having a tattoo P(T) is:

$\\ P(T) = P(T|M)*P(M) + P(T|X)*P(X) + P(T|B)*P(B)$

$\\ P(T) = 0.47*0.22 + 0.36*0.20 + 0.13*0.22$

$\\ P(T) = 0.204$

For non-independent events that happen at the same time, we can say that the probability of occurring simultaneously is:

$\\ P(M \cap T) = P(M|T)*P(T)$

Or

$\\ P(T \cap M) = P(T|M)*P(M)$

But

$\\ P(M \cap T) = P(T \cap M)$

Then

$\\ P(M|T)*P(T) = P(T|M)*P(M)$

We are asked for the probability that a person is a Millennial given or assuming that they have tattoos or P(M | T). Solving the previous formula for the latter:

$\\ P(M|T)*P(T) = P(T|M)*P(M)$

$\\ P(M|T) = \frac{P(T|M)*P(M)}{P(T)}$

We have already know that

$\\ P(T|M) = 0.47\;P(M) = 0.22\;and\;P(T) = 0.204$ .

Therefore

$\\ P(M|T) = \frac{0.47*0.22}{0.204}$

$\\ P(M|T) = 0.50686 \approx 0.51$

Thus, the probability that a person is a Millennial given that they have tattoos is 0.5069 (50.69%) or about 0.51 (51%).

5 0

3 years ago

The answer to number 1

Gnoma [55]

Answer:b

Step-by-step explanation:

8 0

3 years ago

a certain shade of blue is made by mixing 1.5 quarts of blue paint with 5 quarts of white paint. If you need a total of 16.25 ga

Law Incorporation [45]

we know the blue and white paints are on a 1.5 : 5 ratio, thus, if we have a total of 16.25 gallons of paint to be split along that ratio, we can simply divide 16.25 by (1.5+5) and distribute accordingly.

$\bf \cfrac{blue}{white}\qquad \stackrel{ratio}{1.5:5}\qquad \cfrac{1.5}{5}~\hspace{5em}\cfrac{1.5\cdot \frac{16.25}{1.5+5}}{5\cdot \frac{16.25}{1.5+5}}\implies \cfrac{1.5\cdot \frac{16.25}{6.5}}{5\cdot \frac{16.25}{6.5}} \\\\\\ \cfrac{1.5\cdot 2.5}{5\cdot 2.5}\implies \cfrac{3.75}{12.5}\qquad \qquad \boxed{\stackrel{blue}{3.75}~:~\stackrel{white}{12.5}}$

5 0

2 years ago

Use inverse operations to solve the following:<br> 4.9 + z = -9

ale4655 [162]

The answer is z = -13.9

In order to solve this, you need to use inverse operations. The inverse operation of addition is subtraction. So, this is the function we'll use

4.9 + z = -9 ----> subtract 4.9 from both sides

z = -13.9

5 0

3 years ago

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Maurinko [17]

Answer:

The slope is -3/4 and the y-intercept is 1.

Step-by-step explanation:

B is the point where the line cross the y-axis, or vertical axis. Slope is the steepness of the line. Determined by rise over run. When the slope goes down 3 units, the slope goes to the right 4 units.

6 0

2 years ago

Read 2 more answers