the average scores of math students in a certain school is 75 with a standard deviation...

the average scores of math students in a certain school is 75 with a standard deviation of 8.1. one hundred students were randomly selected, and the average score was found to be 71. the director wants to know wether students have deteriorated. significance level is 0.01

1) the hypotheses are ?

2)Decision and conclusion ?

3) the critical value is ?

4) the test statistic is ?

Solutions

Expert Solution

Solution :

The null and alternative hypothesis is ,

H0 : = 75

Ha : 75

Test statistic (t) =

= ( - ) / s / n

= (71 - 75) / 8.1 / 100

Test statistic = -4.94

P-value = 0

= 0.01

P-value <

Reject the null hypothesis .

There is sufficient evidence to support the claim.

orchestra answered 1 year ago

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