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
kirza4 [7]
3 years ago
10

(CO 4) In a sample of 8 high school students, they spent an average of 24.8 hours each week doing sports with a sample standard

deviation of 3.2 hours. Find the 95% confidence interval, assuming the times are normally distributed.
(21.60, 28.00)

(22.12, 27.48)

(22.66, 26.94)

(24.10, 25.50)
Mathematics
1 answer:
AveGali [126]3 years ago
6 0

Answer:  

(22.12, 27.48)

Step-by-step explanation:

Given : Significance level : \alpha: 1-0.95=0.05

Sample size : n= 8 , which is a small sample (n<30), so we use t-test.

Critical values using t-distribution: t_{n-1,\alpha/2}=t_{7,0.025}=2.365

Sample mean : \overline{x}=24.8\text{ hours}

Standard deviation : \sigma=3.2\text{ hours}

The confidence interval for population means is given by :-

\overline{x}\pm t_{n-1,\alpha/2}\dfrac{\sigma}{\sqrt{n}}

i.e. 24.8\pm(2.365)\dfrac{3.2}{\sqrt{8}}

24.8\pm2.67569206001\\\\\approx24.8\pm2.68\\\\=(24.8-2.68, 24.8+2.68)=(22.12, 27.48)

Hence, the 95% confidence interval, assuming the times are normally distributed.=  (22.12, 27.48)

You might be interested in
Help me please [giving brainliest to best answer with step by step]
ollegr [7]

Hi there!

\large\boxed{3\text{ }  \frac{3}{4} cm^3}

Knowing that one cube has side-lengths of 1/2, we can calculate the dimensions for the prism:

Length: 1/2 × 5 = 2.5 cm

Height: 1/2 × 3 = 1.5 cm

Width: 1/2 × 2 = 1 cm

Use this formula to solve for the volume:

V = l × w × h

Thus:

V = 2.5 × 1.5 × 1 = 3.75 cm³

Convert to fraction:

75/100 = 3/4

Thus, the volume in mixed-numbers is 3 3/4 cm³.

7 0
2 years ago
How many solutions does the system of equations have?
Anestetic [448]

Answer:

no solution

Step-by-step explanation:

a solution would mean a point where the two lines cross. theres no such thing for parallel lines.

but if the lines are the same, they are parallel and cross everywhere, that would give infinite solutions.

if they would cross once, it would mean one solution

6 0
2 years ago
Read 2 more answers
If 3X + 2 equals 11, could X equal 5
Norma-Jean [14]

Answer:

No because 3(5) +2= 17

3*5=15

15+2= 17

Step-by-step explanation:

4 0
3 years ago
Read 2 more answers
Apply the distributive property to factor out the GCF.<br><br> 18d + 12= _________
stiv31 [10]

Answer:

6(3d+2)

Step-by-step explanation:

8 0
3 years ago
mary went to her local Zoo where 55% of it's exhibit feature reptiles if the zoo features 20 exhibits in total how many of the z
IceJOKER [234]
Hello!

To find this you have to find what 55% of 20 is

You can do this by doing 20 * 0.55

0.55 is 55% as a decimal

This gives us the answer of 11

Hope this helps!
8 0
3 years ago
Read 2 more answers
Other questions:
  • What is (3x-5)+(-4x+1)
    8·1 answer
  • What is the area of this triangle? A=bh2 54 cm² 90 cm² 108 m² 216 m² Right triangle with height labeled 12 centimeters, base lab
    9·1 answer
  • Which statement is true about angles 3 and 6?
    13·2 answers
  • Carl Carpenter buys a drill press. The price, including tax, is $675.00. He finances the drill press over 24 months after making
    13·1 answer
  • -2x+19+12x=49 solve for x
    5·2 answers
  • Please help! im so confused.
    6·1 answer
  • Need help!!!!!!!!!!!! Struggling
    12·1 answer
  • Mrs. Clark has 7 candy bars to share equally with all the students in his class. He gives each student 1/4 of a bar. None of the
    12·2 answers
  • Plz help me solving this question ​
    14·2 answers
  • "The sum of -9 and -14 " translates to
    6·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!