Question

A standardized test is given to a sixth grade class. Histo deviation of performance may have recently changed. She randomly evidence that the standard deviation of test scores has increa rically, the test scores have had a standard deviation of 21. The believes that the standard sampled 30 students and found a mean of 160 with a standard deviation of 21.3846. Is there sed at the a 0.025 level? Assume the population is normally distributed Step 3 of 5: Determine the value of the test statistic. Round your answer to three decimal places Answer How to e Tables Keypad Previous Step Answers Ho σ 21,1, σ > 21 x2025 = 45.722 Subrnit Answer
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answer:

given data,

  • the class's is grade is sixth
  • the test score of the standard deviation is 21
  • these are she is randomly sampled students is 30
  • these are she  mean is 160
  • these are the standard deviation is 21.3846
  • the standard score of the test score is increased alpha is 0.025

the step 3 of 5

to find the value of the test statistic is.....?

  • the probability is shown in the below step by step,
  • here we need the assumed population normally distribution,
  • here we are know as the values is already ,
  • now we are know as the formula is \chi2 =(n-1)s2/\sigma2,

\Rightarrowthe probability of the value of the test statistic chi square is \chi2 =(n-1)s2/\sigma2

\Rightarrownow substitute the values is in the above formula

\Rightarrow(30-1)*(21.3846/21)^2

\Rightarrow(29)*(1.0183)^2.

\Rightarrow(29)*1.0369

\Rightarrow30.0711

\Rightarrowthere fore 30.0711

30.0711

NOTE: THE GIVEN INFORMATION BASED THESE ARE THE FAINAL ANSWER IS 30.0711

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