1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
vodomira [7]
3 years ago
15

The repair cost of a Subaru engine is normally distributed with a mean of $5,850 and a standard deviation of $1,125. Random samp

les of 20 Subaru engines are drawn from this population and the mean repair cost of each sample is calculated.
Which of the following mean costs would be considered unusual?

A. $6350
B. $6180
C. $5180
D. None of these
Mathematics
1 answer:
Yuri [45]3 years ago
3 0

Answer:

C. $5180

Step-by-step explanation:

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

Normal probability distribution:

Problems of normally distributed samples can be 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.

Z-scores lower than -2 or higher than 2 are considered unusual.

Central limit theorem:

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

In this problem, we have that:

\mu = 5850, \sigma = 1125, n = 20, s = \frac{1125}{\sqrt{20}} = 251.56

Which of the following mean costs would be considered unusual?

We have to find the z-score for each of them

A. $6350

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

By the Central Limit Theorem

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

Z = \frac{6350 - 5850}{251.56}

Z = 1.99

Not unusual

B. $6180

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

Z = \frac{6180 - 5850}{251.56}

Z = 1.31

Not unusual

C. $5180

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

Z = \frac{5180 - 5850}{251.56}

Z = -2.66

Unusual, and this is the answer.

You might be interested in
What is the value of y when -5 =<br> = y - 7?<br> 9<br> a. -7<br> b.-11<br> C. -38<br> d. -52
weqwewe [10]

Answer:

2

Step-by-step explanation:

You have to cancel the -7 so you would add +7 to each side.

-7+7=0, -5+7= 2

y=2

Although this isn't an answer choice. Did you mistype something?

8 0
3 years ago
Dawson says that the expression (2 4/10+8 4/5(
Katen [24]

Answer:

56/5

Step-by-step explanation:

2 4/10=24/10

8 4/5=44/5

24/10+44/5=24/10+88/10=112/10=56/5

7 0
3 years ago
Unicorns can live forever but they remain children for 261 months. How many years is that in total?
11111nata11111 [884]

Answer:

21.75 years (Almost 22 years)

21 years and 9 months. :)

Step-by-step explanation:

There are 12 months in a year.

261/12 = 21.75

.75 = 3/4

3/4(12) = 9 months

Hope that helps!

6 0
2 years ago
1 point
Serga [27]

Answer:

I do not know

Step-by-step explanation:

6 0
2 years ago
Write out a equation of a line which has a slope of 2
butalik [34]

Answer:

There are many lines with slopes of 2. When writing them, they simply need to be y = 2x + b, with which b can be any number.

Step-by-step explanation:

We know this because slope intercept form is y = mx + b, in which m is the slope of the equation.

4 0
3 years ago
Other questions:
  • If a bag contains 4 blue marbles, 8 red marbles, and 2 green marbles, what is the probability of pickibg a marble that is nit gr
    9·1 answer
  • What is the square root of 293
    15·1 answer
  • Tickets for the homecoming football game are being sold for $12 for alumni and $7 for students. The stadium holds a maximum of 5
    13·1 answer
  • Mrs. Sawyer estimates that a quiz will take students no fewer than 11 minutes but no more than 41 minutes to complete. She allot
    8·2 answers
  • Please Please Pleaseeeeeeeeee help me out with this question.
    15·2 answers
  • Ways to end Maltreatment towards women
    6·1 answer
  • HELLPPPP MEEEEEE please!!!!!
    10·1 answer
  • katy desea alquilar un barca y gastar por menos $54. El barco cuesta $7 por hora y katy tiene un cupom de descuento de $9 dolare
    5·1 answer
  • Ms. Trimmer paid $65 last year for her subscription to Drama Teachers Monthly. This year the fee is $78. What rate of increase i
    15·2 answers
  • Arrange the numbers in the ascending order: 3/4,1/12,9/16,7/24
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!