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2 years ago

Which of the following is a Type I error?

1 answer:

3 0

Answer:

C. The president rejects the hypothesis that the proportion of students who earn a bachelor's degree within six years is 0.398, when, in fact, the proportion is 0.398.

Step-by-step explanation:

A type I error occurs if you reject the null hypothesis when it is true.

Now the hypotheses are:

$H_0:$ The proportion is 0.398

$H_1:$ The proportion is less than 0.398

If in actual fact the proportion is 0.398, then the president must not reject the $H_0$ .

This is a correct decision.

If in actual fact the proportion is 0.398, and the president rejects the $H_0$ , then a type I error is committed.

The correct choice is C.

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Which expression is equivalent to 4(m+5)?

Taya2010 [7]

The answer is b 4m+20

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3 years ago

Read 2 more answers

An article includes the accompanying data on compression strength (lb) for a sample of 12-oz aluminum cans filled with strawberr

Veseljchak [2.6K]

Answer:

The calculated value |t| = 2.375 > 2.1009 at 0.05 level of significance

Null hypothesis is rejected 

Alternative hypothesis is accepted

The extra carbonation of cola results in a higher average compression strength

Step-by-step explanation:

Step(i):-

Given data

First sample size (n₁) = 10

mean of the first sample(x₁⁻) = 537

standard deviation of the first sample (S₁) = 22

second sample size (n₂) = 10

mean of the second sample (x₂⁻) = 559

standard deviation of the second sample (S₂) = 17

Step(ii):-

Null hypothesis : H₀:- The extra carbonation of cola results in a lower average compression strength

Alternative Hypothesis :H₁

The extra carbonation of cola results in a higher average compression strength

Step(iii):-

By using student's t -test for difference of means

Test statistic

  $t = \frac{x^{-} _{1}-x^{-} _{2} }{\sqrt{S^{2} (\frac{1}{n_{1} }+\frac{1}{n_{2} } } )}$ 

 where 

  $S^{2} = \frac{n_{1}S^{2} _{1} + n_{2} S_{2} ^{2} }{n_{1}+n_{2} -2 }$ 

  $S^{2} = \frac{10(22)^{2} + 10 (17) ^{2} }{10+10 -2 } = \frac{ 7730}{18} = 429.4$ 

  $t = \frac{537-559 }{\sqrt{429.4 (\frac{1}{10 }+\frac{1}{10 } } )}$ 

 t = -2.375

|t| = |-2.375| = 2.375

Degrees of freedom

γ = n₁+n₂ -2 = 10+10-2 =18

 $t_{\frac{\alpha }{2} ,n-1}=t_{(\frac{0.05}{2} ,18)} = t_{(0.025,18)}}=2.1009$ 

The calculated value |t| = 2.375 > 2.1009 at 0.05 level of significance

Null hypothesis is rejected 

Alternative hypothesis is accepted

Final answer:-

The extra carbonation of cola results in a higher average compression strength

 

5 0

2 years ago

Wilbur spends 2/3 of his income, share 1/12, and saves the rest. What part of his income does he save? Give the answer in simple

scoundrel [369]

Answer:

1/4 of his income.

Step-by-step explanation:

If Wilbur spends 2/3 of his income, 1/3 or 4/12 of it is left for other purposes (It is easier if everything has a common denominator of 12). And if he shares 1/12 of that remaining amount, there is 3/12 left. And when we simplify 3/12, we get 1/4.

*Mark me brainliest!*

7 0

3 years ago

a coin operated machine sells plastic rings . it contains 6 yellow rings,11 blue rings,15 green rings,and 3 black rings.sarah pu

Mariana [72]

Sample space ={6y+11b+15g+3bk} = 35 elements
number of black rings=3
probability (black ring) =3/35=0.085

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2 years ago

What is the slope of the line that contains the points (-4,2) and (6,-3)?-

schepotkina [342]

Answer:

Step-by-step explanation: