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
sasho [114]
2 years ago
14

5.44 Teaching descriptive statistics: A study compared five different methods for teaching descriptive statistics. The five meth

ods were traditional lecture and discussion, programmed textbook instruction, programmed text with lectures, computer instruction, and computer instruction with lectures. 45 students were randomly assigned, 9 to each method. After completing the course, students took a 1-hour exam. (a) What are the hypotheses for evaluating if the average test scores are different for the different teaching methods?
Mathematics
1 answer:
maria [59]2 years ago
7 0

Answer:

The null hypothesis is that all the different teaching methods have the same average test scores.

H0: μ1 = μ2 = μ3 = μ4 = μ5

The alternative hypothesis is that at least one of the teaching methods have a different mean.

Ha: at least one mean is different. (μ1 ≠ μi)

Step-by-step explanation:

The null hypothesis (H0) tries to show that no significant variation exists between variables or that a single variable is no different than its mean. While an alternative Hypothesis (Ha) attempt to prove that a new theory is true rather than the old one. That a variable is significantly different from the mean.

For the case above, let μ represent the average test scores for the teaching methods:

The null hypothesis is that all the different teaching methods have the same average test scores.

H0: μ1 = μ2 = μ3 = μ4 = μ5

The alternative hypothesis is that at least one of the teaching methods have a different mean.

Ha: at least one mean is different. (μ1 ≠ μi)

You might be interested in
A major purpose of preparing closing entries is to a) adjust the asset accounts to their correct current balances. b) update the
babunello [35]

Answer:

b) update the Retained Earnings account.

Step-by-step explanation:

A major purpose of preparing closing entries is to -  update the Retained Earnings account.

Retained earnings are defined as those profits, that a company has earned to date minus any dividends or other money paid to investors.

Whenever we make an entry to the accounting records, that affects a revenue or expense account, this retained earning amount is adjusted.

5 0
3 years ago
Imagine that you are standing at the top of a cliff that is 1,500 feet above sea level. You see ship A, and your eyes make an an
kati45 [8]
Answer: option A. 30 °.

Explanation:

1) Draw this triangle: Eyes - Ship A - height of the cliff:

The angle of the vertix where the eyes are is: 90° - depreesion angle = 90° - 60° = 30°.

2) opossite leg = horizontal distance to the ship A = x

3) adjacent leg = height of the cliff = 1500 feet

4) tan(30°) = x / 1500 feet => x = 1500 tan(30°) = 1500 √3 / 3 = 500√3

5) Draw the triangle of the eyes - ship B - hieght of the cliff

6) The unknown is the depression angle of the eyes with ship B, α

7) opposite leg = 500√3 feet + 1000√3 feet = 1500√3 feet

8) adjacent leg = height of the cliff = 1500 feet

9) tan(α) = opposite leg / adjacent leg = 1500√3 / 1500 = √3

10) α = arctan(√3) = 60°

11) Depression angle = 90° - 60° = 30° Which is the answer

5 0
3 years ago
Read 2 more answers
2.3 repeating as a fraction​
Marat540 [252]
23/10 = 2 and 3/10




I hope this helped
7 0
3 years ago
Read 2 more answers
Calculating the degrees of freedom, the sample variance, and the estimated standard error for evaluations using the t statistic
Yuliya22 [10]

Answer:

a) For the first part we have a sample of n =10 and we want to find the degrees of freedom, and we can use the following formula:

df = n-1= 10-1=9

d.9

b) s^2 = \frac{SS}{n-1}= \frac{600}{41-1}= 15

a.15

c) For this case we have the sample size n = 25 and the sample variance is s^2 =400 , the standard error can founded with this formula:

SE = \frac{s^2}{\sqrt{n}}= \frac{400}{\sqrt{25}}= 80

Step-by-step explanation:

Part a

For the first part we have a sample of n =10 and we want to find the degrees of freedom, and we can use the following formula:

df = n-1= 10-1=9

d.9

Part b

From a sample we know that n=41 and SS= 600, where SS represent the sum of quares given by:

SS = \sum_{i=1}^n (X_i -\bar X)^2

And the sample variance for this case can be calculated from this formula:

s^2 = \frac{SS}{n-1}= \frac{600}{41-1}= 15

a.15

Part c

For this case we have the sample size n = 25 and the sample variance is s^2 =400 , the standard error can founded with this formula:

SE = \frac{s^2}{\sqrt{n}}= \frac{400}{\sqrt{25}}= 80

8 0
3 years ago
People use water to​ cook, clean, and drink every day. An estimate of 33.9​% of the water used each day is for cooking. If a fam
Lady_Fox [76]

Answer:

23 gallons of water

Step-by-step explanation:

People use water to​ cook, clean, and drink every day. An estimate of 33.9​% of the water used each day is for cooking. If a family uses 67.8 gallons of water a day for cooking​, how many gallons do they use every​ day?

This is calculated as:

33.9 % × 67.8 gallons of water

= 0.339 × 67.8 gallons of water

= 22.9842 gallons of water

Approximately = 23 gallons of water

Therefore, 23 gallons of water are used everyday for cooking

5 0
2 years ago
Other questions:
  • What is an equation of the line that passes through the points (3,1) and (6, 6)? Put your answer in fully reduced form.​
    7·1 answer
  • What is the equation of a line that passes through (4, 7) and has a slope of −14?
    12·1 answer
  • ANSWER QUICK PLEASE HELP
    5·1 answer
  • Let A = {10, 20, 30, 40, 50, 60} and B = {10, 40, 60}. What is A ∩ B?
    8·1 answer
  • Fill in the table using this function rule.<br> y=4+2x<br> X Y<br> 5<br> 7<br> 9<br> 10
    11·2 answers
  • Need help with us question
    13·1 answer
  • I will give brainleist! Please help on all it’s my homework i don’t know how to do
    5·2 answers
  • For a quadrilateral to be a rhombus, the diagonals __ and __.
    5·1 answer
  • Operación 1: (6+(4*12)/12-2)+5​
    14·1 answer
  • Convert 35 miles per gallon to kilometers per liter.
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!