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
AveGali [126]
3 years ago
12

In a random sample of 8 ​people, the mean commute time to work was 35.5 minutes and the standard deviation was 7.4 minutes. A 90

​% confidence interval using the​ t-distribution was calculated to be (30.5,40.5). After researching commute times to​ work, it was found that the population standard deviation is 9.3 minutes. Find the margin of error and construct a 90​% confidence interval using the standard normal distribution with the appropriate calculations for a standard deviation that is known. Compare the results.
Mathematics
1 answer:
konstantin123 [22]3 years ago
4 0

Answer:

Margin of Error = 5.4088 ;

Confidence interval = (30.1 ; 40.9)

Interval estimate are almost the same

Step-by-step explanation:

Given that :

Population standard deviation, σ = 9.3

Sample size, n = 8

Xbar = 35.5

Confidence level = 90%

The confidence interval:

Xbar ± Margin of error

Margin of Error = Zcritical * σ/sqrt(n)

Zcritical at 90% = 1.645

Margin of Error = 1.645 * 9.3/sqrt(8) = 5.4088

Confidence interval :

Xbar ± Margin of error

35.5 ± 5.4088

Lower boundary = (35.5 - 5.4088) = 30.0912 = 30.1

Upper boundary = (35.5 + 5.4088) = 40.9088 = 40.9

(30.1 ; 40.9)

T distribution =. (30.5 ; 40.5)

Normal distribution = (30.1, 40.9)

You might be interested in
The product of 9 and number (x) is 88. Which equation shows this relationship?
Digiron [165]
This equation is
9*x =88
5 0
3 years ago
What is 9.15 to the nearest tenth
tiny-mole [99]
The answer is 9.2, because when the number behind the number being rounded is 5 or above, you round up. if the number was 9.14, it would be rounded down to 9.1 :)
6 0
2 years ago
5x+5=1/2x-4 , what is x
melomori [17]

The answer is x = -2. The steps are in the image below.

Hope this helps!!!!!!!!

Please give me brainliest!!!!!!!!!!!

8 0
2 years ago
Read 2 more answers
Erica and Amy started biking in the opposite directions at the same time from the same place. Erica biked at a speed of 6 meters
ipn [44]
Since they are moving in opposite directions, this is the same as Amy staying still and Erica biking at 10 meters per second away from her.

To travel 1km = 1000m at 10 meters per second, you need 1000/10 = 100 seconds.
3 0
3 years ago
For the following right triangle, find the side length x.​
never [62]

Answer:

x = 10

Explanation:

Using Pythagoras Theorem:

  • a² + b² = c²

Solve:

8² + 6² = x²

x² = 64 + 36

x² = 100

x = √100

x = 10

8 0
2 years ago
Read 2 more answers
Other questions:
  • Need help on this question. How do you find x?
    11·1 answer
  • 783/32 as a mixed number
    15·2 answers
  • Michael graphs the equations y= -1/2+4 and y = x + 1 to solve the equation -1/2x+4= x+1. His graph is shown below. What are the
    12·1 answer
  • How many millimetres are there in 5 and a half litres
    15·1 answer
  • Can someone help please ​
    9·2 answers
  • Pls help with math ASAP
    7·1 answer
  • HELP ASAP!!! i have an assigment and i dont get number 1. please if you're smart do it. I'm giving brainliest!!
    10·1 answer
  • There are 347 students going on a field trip. Each bus holds 44 students. If each bus costs $95, is the total cost of the buses
    14·1 answer
  • Heeeeeeeeeeeeelp!?!?!?!?!?!?!?!?!?!?!?!
    5·2 answers
  • The product of 1/2 and 2/15 is a/an ________________.
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!