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
Ludmilka [50]
2 years ago
11

Construct a 95% confidence interval for the population mean, µ. Assume the population has a normal distribution. A sample of 25

randomly selected students has a mean test score of 81.5 with a standard deviation of 10.2. a. (66.35, 69.89) b. (56.12, 78.34) c. (77.29, 85.71) d. (87.12, 98.32)
Mathematics
1 answer:
bixtya [17]2 years ago
6 0

Answer:C. (77.29, 85.71)

Step-by-step explanation:

We want to determine a 95% confidence interval for the mean test score of randomly selected students.

Number of sample, n = 25

Mean, u = 81.5

Standard deviation, s = 10.2

For a confidence level of 95%, the corresponding z value is 1.96. This is determined from the normal distribution table.

We will apply the formula

Confidence interval

= mean +/- z ×standard deviation/√n

It becomes

81.5 +/- 1.96 × 10.2/√25

= 81.5 +/- 1.96 × 2.04

= 81.5 +/- 3.9984

The lower end of the confidence interval is 81.5 - 3.9984 =77.5016

The upper end of the confidence interval is 81.5 + 3.9984 =85.4984

Therefore, the correct option is

C. (77.29, 85.71)

You might be interested in
If ava makes $15 in 2 hours, what is her rate of pay?
zalisa [80]

Answer:

$7.50 per hour

Step-by-step explanation:

15/2=7.5

7 0
3 years ago
Read 2 more answers
Natalia is calculating the areas of parallelograms using the following formula: Area=bh, where b represents the base of the para
lions [1.4K]
4 inches think you believe in yourself
3 0
2 years ago
8 + 3x=29 +2x <br> I need answer ASAP
borishaifa [10]

Answer:

x = 21

Step-by-step explanation:

8 + 3x = 29 + 2x

8 + 3x - 2x = 29

8 + x = 29

x = 29 - 8 = 21

x = 21

3 0
2 years ago
I'm in 7th grade and need help have a final tomorrow
inna [77]
I can maybe help, what's the question
7 0
3 years ago
Explain how you would round the numbers 33 and 89 to estmate their sum
ValentinkaMS [17]
Well 33 is rounded down to 30

And 89 is rounded up to 90

So it would be 120

Anything from 1-4 is rounded down and anything 5-9 is rounded up
8 0
3 years ago
Read 2 more answers
Other questions:
  • What is 100/45 in a mixed number
    11·1 answer
  • Someone help me I will mark you the brainiest
    12·1 answer
  • draw a rectangle and another figure that is not a rectangle by tracing lines on a grid paper.describe how to find the perimeter
    15·1 answer
  • What is the value of x?
    8·1 answer
  • What number must be added to the polynomial to complete the square? If necessary, use the slash mark ( / ) as a fraction bar and
    10·1 answer
  • Which equation could be represented by the number line
    8·1 answer
  • There is a leak in the ceiling due to snow. John is planning to use a bowl
    9·1 answer
  • Use simple interest to find the ending balance<br>$14,000 at 6% for 9 years​
    14·1 answer
  • Please help, would be greatful :)
    8·2 answers
  • Help me pls. not links pls
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!