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
inessss [21]
3 years ago
13

Suppose scores on exams in statistics are normally distributed with an unknown population mean and a population standard deviati

on of three points. A random sample of 36 scores is taken and gives a sample mean (sample mean score) of 68. Find a confidence interval estimate for the population mean exam score (the mean score on all exams). Find a 90% confidence interval for the true (population) mean of statistics exam scores.
Mathematics
1 answer:
Anna71 [15]3 years ago
8 0

Answer:

( 67.18, 68.82)

Step-by-step explanation:

Let \mu be the true (population) mean of statistics exam scores. We have a large random sample of n = 36 scores with a sample mean (sample mean score) of \bar{x} = 68. We know that the population standard deviation is \sigma = 3. A pivotal quantity is (\bar{x}-\mu)/(3/\sqrt{36}) = (\bar{x}-\mu)/(3/6) = (68-\mu)/(1/2) which is approximately normally distributed and P(-z_{0.05}\leq(68-\mu)/(1/2)\leq z_{0.05}) = 0.90 where -z_{0.05} =-1.6449, and so, P(-1.6449\leq(68-\mu)/(1/2)\leq 1.6449) = 0.90. Therefore the 90% confidence interval is (68-(1/2)(1.6449), 68+(1/2)(1.6449)), i.e., ( 67.18, 68.82)

You might be interested in
What the slope of 3,4 7,-4
Trava [24]

Answer: The slope is  -2

5 0
3 years ago
Help me please i will mark brainliest if correct
iren2701 [21]

Answer:

7 x 2 + 31

Step-by-step explanation:

Equals to the bottom line answer is 7

7 0
2 years ago
Pls help I’m on my last attempt to answer this question. This is geometry
Harman [31]

Answer:

the answer to this question would be RT=16 Please mark brainliest!

5 0
2 years ago
Amber, Bernie, and Carlos are working on a problem together. Their goal is to correctly apply the difference of cubes formula to
NeX [460]

Answer: Carlos is correct

Step-by-step explanation:

2x^5-250x^2

The first step is to factorize out 2x^2

2x^2(x^3-125)

This can be rewritten as

2x^2(x^3-5^3),

Recall, difference if cube (a^3-b^3)

= (a-b)(a^2 +ab + b^2)

from our equation,

a= x

b = 5.

So the difference of cubes will be

2x^2[(x-5) (x^2 + 5x + 5^2)]

=2x^2[(x-5) (x^2 + 5x + 25)]

Carlos followed these steps. So he is correct. Carlos is correct because he correctly factored the GCF, identified a and b, and applied the difference of cubes method.

Amber is incorrect because 125 is equal to b3, not b.

Bernie is incorrect because x2 is not the GCF of the polynomial. The GCF is 2x^2.

6 0
3 years ago
2 Which expression is equivalent to 64-*?
Rasek [7]

Answer:

2

Step-by-step explanation:

(8-x)(8+x)

8×8=64

-x·+x=-x^2

64-x^2

3 0
2 years ago
Other questions:
  • 6cm : 3cm in lowest form
    10·1 answer
  • Find the interest. Round to the nearest cent.<br><br> $1850 at 8% for 14 months
    14·1 answer
  • How to solve b/2= -4
    15·1 answer
  • A^2 + 6ab for a=-3 and b=4
    7·1 answer
  • Find the next three terms of the sequence: 33, 25, 18, 12, …….
    6·1 answer
  • Tanyas baked goods took in 175$ To help raise money for the chorus club .Tanya need to spend 32$ for baking supplies write and e
    14·1 answer
  • If x=3 and y=7, evaluate the following expression: 100 − 3 ( 3 − 4x )
    10·2 answers
  • On a softball field, home plate is 43 feet from the pitcher’s mound. A ball is hit at an angle of 27° east of the pitcher’s moun
    8·2 answers
  • Carolina has built her dog bed that is 2 1/8 feet wide and 5 1/3 feet long. Find the area of the bed
    7·1 answer
  • What are the zeros for each function ? f(x) = 2(x+1)(x-3)(x-1) ^2 (squared)
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!