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
alina1380 [7]
3 years ago
9

Denise is a professional swimmer who trains, in part, by running. she would like to estimate the average number of miles she run

s in each week. for a random sample of 20 weeks, the mean is = 17.5 miles with standard deviation s = 3.8 miles. find a 99% confidence interval for the population mean number of miles denise runs. use a graphing calculator for this one and not the t chart from the book.
Mathematics
1 answer:
SSSSS [86.1K]3 years ago
4 0
Given:
n = 20, sample size
xbar = 17.5, sample mean
s = 3.8, sample standard deiation
99% confidence interval

The degrees of freedom is 
df = n-1 = 19

We do not know the population standard deviation, so we should determine t* that corresponds to df = 19.
From a one-tailed distribution, 99% CI means using a p-value of 0.005.
Obtain
t* = 2.8609.

The 99% confidence interval is
xbar +/- t*(s/√n)

t*(s/√n) = 2.8609*(3.8/√20) = 2.4309
The 99% confidence interval is
(17.5 - 2.4309, 17.5 + 2.4309) = (15.069, 19.931)

Answer: The 99% confidence interval is (15.07, 19.93)
You might be interested in
Grade 4
Lesechka [4]
The largest is 17.08
thank me later :)
6 0
3 years ago
Which is a closer estimate of pi? Explain your answer.
nydimaria [60]
The fraction 22/7 has a value of 3.142857, so it has the same first three digits as pi. Both 3.14 and 22/7 are approximations of pi. In fact, 22/7 is close to pi than 3.14 is. Pi is irrational. That is, the decimal expansion never ends and never repeats, so any number of decimal places we wrote out is an approximation. The approximation 3.14 is about 1/2 percent off from the true value, and the fairly well know 3.141559 is within 0.000084 percent.
6 0
3 years ago
Your family drives from Austin Texas to Tampa Florida. The trip is 1145 mi and lasts four days. How many miles should your famil
Colt1911 [192]
286.2...round down soo...286 miles
5 0
3 years ago
Suppose AP = 2 cm and BQ = 7 cm. What is the length of PC?
viktelen [127]

Step-by-step explanation:

is this a quadrilateral? or polygon or triangle?

what are the angles (I believe there should be at least an angle given) else PC can be any value that is positive

3 0
3 years ago
I’ll make brainly if the answer is right
puteri [66]
The answer is A; 1/2. You add 1 1/2 and 1 1/2 together to get 3. Then you subtract 3 1/2 and 3 to get your answer 1/2. I hope that helps!
6 0
3 years ago
Other questions:
  • Fun center rents popcorn machines for $20 per hour. In addition to the hourly charge, there is a rental fee of $32. Is the numbe
    12·1 answer
  • WHO EVER ANSWERS FIRST GETS BRAINLIEST
    8·1 answer
  • Find tan Ø, given that sin Ø = - 4/5 and cos Ø>0.
    10·1 answer
  • What type of number is -2343
    14·1 answer
  • Solve for x
    7·1 answer
  • What is the sum of the polynomials?<br> (7x2 - 4x) + (2x - 4x4)
    9·1 answer
  • In 28 years a man will be twice as old as he will be in 2 years. How old is he now?<br> +
    14·2 answers
  • PLSSSSSSSSS I WILI WILL GIVE BRAINLIEST PLSSSSSSSSSSS
    12·1 answer
  • &gt;
    5·1 answer
  • Instructions: Find the missing length indicated.<br> 400<br> 144<br> X
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!