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
zepelin [54]
3 years ago
6

An educational psychologist wishes to know the mean number of words a third grader can read per minute. She wants to make an est

imate at the 85% level of confidence. For a sample of 295 third graders, the mean words per minute read was 26.9. Assume a population standard deviation of 2.7. Construct the confidence interval for the mean number of words a third grader can read per minute. Round your answers to one decimal place
Mathematics
1 answer:
MrRa [10]3 years ago
7 0

Answer:

<em> 85% level of the confidence interval is</em>

<em>(26.337, 26.662)</em>

Step-by-step explanation:

<u><em>Explanation</em></u>:-

Given the size of the sample 'n' = 295

Mean of the sample x⁻ = 26.5

The Standard deviation of the Population = 2.7

85% level of the confidence interval is determined by

(x^{-} - Z_{0.15} \frac{S.D}{\sqrt{n} } , x^{-} + Z_{0.15} \frac{S.D}{\sqrt{n} })

Critical value Z₀.₁₅ = 1.036

<em> 85% level of the confidence interval is determined by</em>

(x^{-} - Z_{0.15} \frac{S.D}{\sqrt{n} } , x^{-} + Z_{0.15} \frac{S.D}{\sqrt{n} })

(26.9 -1.036 \frac{2.7}{\sqrt{295} } , 26.5 + 1.036 \frac{2.7}{\sqrt{295} })

( 26.5 - 0.1628 , 26.5+0.1628)

(26.3372,26.6628)

You might be interested in
Please help!<br> Quickly!
ss7ja [257]
The last one is the last correct answer that needs to be checked!!
8 0
3 years ago
Five years ago, the population of a city was 49,000. each year the zoning commission permits an increase of 580 in the populatio
Paladinen [302]

The maximum population be 5 year from now will be 54,800 given that five years ago, the population of a city was 49,000 and each year the zoning commission permits an increase of 580 in the population. This can be obtained using the formula of arithmetic progression.

<h3>What will the maximum population be 5 year from now?</h3>

Formula of arithmetic progression is given by,

⇒ aₙ = a + (n - 1)d

where aₙ = nth term, a = first term, d = common difference

Here in the question it is given that,

  • Five years ago, the population of a city was 49,000
  • Each year the zoning commission permits an increase of 580 in the population

   

We have to find out the maximum population in 5 year from now.

By using the formula of arithmetic progression we get,

aₙ = a + (n - 1)d,

here in the question,

  • a = 49,000,
  • n = five years ago + current year + five years from now ⇒ n = 5 + 1 + 5         ⇒ n = 11g
  • d = 580

Now we get,

⇒ aₙ = a + (n - 1)d

⇒ aₙ = 49000 + (11 - 1)580

⇒ aₙ = 49000 + (10)580

⇒ aₙ = 49000 + 5800

⇒ aₙ = 54,800

Hence the maximum population be 5 year from now will be 54,800 given that five years ago, the population of a city was 49,000 and each year the zoning commission permits an increase of 580 in the population.

Learn more about arithmetic progression here:

brainly.com/question/16954227

#SPJ4

8 0
1 year ago
What is (-0.8)(-0.8)(-0.8)
puteri [66]
The answer would be -0.512
You would get this answer because -0.8 times -0.8 equals 0.64. Positive 0.64 times negative 0.8 would result In -0.512
8 0
3 years ago
Read 2 more answers
What are the x-intercepts of the graphed function?
Vlad [161]

Answer:

Step-by-step explanation:

d

8 0
3 years ago
Read 2 more answers
china receives a shipment of 125 dishes in 5 boxes, at this rate how many dishes will it receive in 15 boxes
Elena-2011 [213]
Simple....

in 5 boxes you have 125 dishes...how many per box?

125/5=25

So, how many dishes in 15 boxes?

25*15=375

This means that in 15 boxes there are 375 dishes.

Thus, your answer.
6 0
3 years ago
Read 2 more answers
Other questions:
  • If a ball is thrown off a 123m cliff at a speed of 18m/s ,how far from the base of the cliff is the ball ? SHOW STEPS ILL GIVE B
    10·1 answer
  • What are the domain and range of the logarithmic function f(x) = log7x?
    6·1 answer
  • What is the simplified form of x minus 5 over x squared minus 3x minus 10 ⋅ x plus 4 over x squared plus x minus 12? (6 points)
    9·2 answers
  • Joe is working on a school report in a word processor she wants to place an oversized image which is 30.51 cm wide so that it ap
    6·2 answers
  • a fraction has a denominator that is 4 greater than its numerator. it is equivalent to 9/15. what is the fraction?
    11·1 answer
  • Find the distance between k and l
    6·2 answers
  • Circumference and area of a circle (picture provided)
    10·1 answer
  • Money that you save in a bank account can grow. Money that you borrow from a bank is not free.
    14·1 answer
  • HELPPP ASAPPPPPPPPPPP
    5·1 answer
  • 5-2x &gt; 3x-10<br><br> Solve the inequality
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!