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aliina [53]
2 years ago
7

25 scores from all of the students who took the test. She sees that the mean score is 134 with a standard deviation of 6.0547. T

he superintendant wants to know if the standard deviation has changed this year. Previously, the population standard deviation was 13. Is there evidence that the standard deviation of test scores has decreas
Mathematics
1 answer:
Tomtit [17]2 years ago
7 0

Answer:

WE fail to reject the Null and conclude that ; Standard deviation of test hasn't decreased.

Step-by-step explanation:

The hypothesis :

H0 : σ = 13

H1 : σ < 13

Using the Chisquare Square statistic :

χ² = (n-1)*s²/σ²

Sample size, n = 25

s² = 6.0547²

σ² = 13²

χ² = (25 - 1)*6.0547² / 13²

χ² = 879.82541016 / 169

χ² = 5.206

The degree of freedom, df = 25 - 1 = 24

The Pvalue(5.206, 24) = 0.99981

Reject H0, if Pvalue < α ;

Since Pvalue > α ; WE fail to reject the Null and conclude that ; Standard deviation of test hasn't decreased.

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AleksAgata [21]

Answer:

6/-4   (right 6 points on x-axis & down 4 points on y- axis

Step-by-step explanation:

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---------- =    ------

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7 0
2 years ago
In the given diagram , TY is a tangent to the circle TVS . If &lt;SVT = 48° and |VS| = |ST| . What is &lt; VTY.​
ycow [4]

Answer:

  • 84°

Step-by-step explanation:

∠VTY is the tangent chord angle

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ΔTVS is isosceles as VS = ST, therefore the opposite angles are same.

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<u>The measure of angle S</u>

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<u>The required angle</u>

  • m∠VTY = 84°
4 0
3 years ago
Read 2 more answers
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just olya [345]
I'm not completely sure but this is what I would do.
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Answer:

Step-by-step explanation:

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Bad White [126]

Answer:

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Step-by-step explanation:

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3 years ago
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