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3 years ago

8

A normal population has a mean m=33 and standard deviation s = 9. What is the probability that a randomly chosen value will be

greater than 44?

1 answer:

Sonja [21]3 years ago

5 0

55 I actually don’t know the real answer

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What is the equation of a horizontal line passing through the point (1, 14)?

Klio2033 [76]

The equation line passing through a point is understood to be parallel to the x-axis. In this case, the equation should be expressed as y = b where b is any number. Since y = 14 in the point (1,14), the equation of horizontal line passing through this point is y = 14.

3 0

3 years ago

Read 2 more answers

How do you solve the literal equation <br><br> W > Y + H for H?<br> P

monitta

Subtract Y from both sides

H < W - Y

5 0

3 years ago

The time needed to complete a final examination in a particular college course is normally distributed with a mean of 77 minutes

Komok [63]

Answer:

a. The probability of completing the exam in one hour or less is 0.0783

b. The probability that student will complete the exam in more than 60 minutes but less than 75 minutes is 0.3555

c. The number of students will be unable to complete the exam in the allotted time is 8

Step-by-step explanation:

a. According to the given we have the following:

The time for completing the final exam in a particular college is distributed normally with mean (μ) is 77 minutes and standard deviation (σ) is 12 minutes

Hence, For X = 60, the Z- scores is obtained as follows:

Z= X−μ /σ

Z=60−77 /12

Z=−1.4167

Using the standard normal table, the probability P(Z≤−1.4167) is approximately 0.0783.

P(Z≤−1.4167)=0.0783

Therefore, The probability of completing the exam in one hour or less is 0.0783.

b. In this case For X = 75, the Z- scores is obtained as follows:

Z= X−μ /σ

Z=75−77 /12

Z=−0.1667

Using the standard normal table, the probability P(Z≤−0.1667) is approximately 0.4338.

Therefore, The probability that student will complete the exam in more than 60 minutes but less than 75 minutes is obtained as follows:

P(60<X<75)=P(Z≤−0.1667)−P(Z≤−1.4167)

=0.4338−0.0783

=0.3555

Therefore, The probability that student will complete the exam in more than 60 minutes but less than 75 minutes is 0.3555

c. In order to compute how many students you expect will be unable to complete the exam in the allotted time we have to first compute the Z−score of the critical value (X=90) as follows:

Z= X−μ /σ

Z=90−77 /12

Z=1.0833

UsING the standard normal table, the probability P(Z≤1.0833) is approximately 0.8599.

Therefore P(Z>1.0833)=1−P(Z≤1.0833)

=1−0.8599

=0.1401

Therefore, The number of students will be unable to complete the exam in the allotted time is= 60×0.1401=8.406

The number of students will be unable to complete the exam in the allotted time is 8

6 0

3 years ago

A firm’s marketing manager believes that total sales for next year will follow the normal distribution, with a mean of $3.2 mill

klasskru [66]

Answer:

The sales level that has only a 3% chance of being exceeded next year is $3.67 million.

Step-by-step explanation:

When the distribution is normal, we use 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 question, we have that:

In millions of dollars,

$\mu = 3.2, \sigma = 0.25$

Determine the sales level that has only a 3% chance of being exceeded next year.

This is the 100 - 3 = 97th percentile, which is X when Z has a pvalue of 0.97. So X when Z = 1.88.

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

$1.88 = \frac{X - 3.2}{0.25}$

$X - 3.2 = 0.25*1.88$

$X = 3.67$

The sales level that has only a 3% chance of being exceeded next year is $3.67 million.

7 0

3 years ago

At the bakery ratio of cookie sales to donut sales is 4 to 3.Cookies and donuts cost the same amount.If the bakery earned 375.00

Oksanka [162]

3:7 = X:375
375/7 = 53.57
53.57×3 = 160.71

8 0

3 years ago