Amanager is interested in determining if the population standard deviation has dropped below 134. based on a sample of n=27 items selected randomly from the population, conduct the appropriate hypothesis test at a 0.05 significance level. the sample standard deviation is 126. determine the null and alternative hypothese

H₀: σ² ≥ 17956

H₁: σ² < 17956

Step-by-step explanation:

Hello!

You are asked to test if the population standard deviation of a certain population. Now keep in mind that wherever you want to make a hypothesis test for a population parameter, you have to have a known distribution that includes this parameter. Since the population standard deviation is no parameter of any distribution, what you have to do is test the population variance. Any decision you make about the population variance can be extrapolated to the population standard deviation.

To make a hypothesis test for the population variance, you need a variable with normal distribution and the statistic to use is a Chi-square statistic.

The hypothesis is that the population standard deviation is less than 134, symbolically: σ < 134

Translated in terms of the population variance: σ² < 17956

H₀: σ² ≥ 17956

H₁: σ² < 17956

α: 0.05

χ²=  (n-1)S²  ~χ²

σ²

χ²=  (27-1)(126)²  = 22.988

17956

The test is one tailed (left)

χ² =χ² = 15.379

If the calculated Chi-square value is ≤ than the critical value, you reject the null hypothesis.

If the calculated Chi-square value is > than the critical value, you don't reject the null hypothesis.

Since the value is greater than the critical value, you do not reject the null hypothesis. So at a 5% level, there is not enough evidence to reject the null hypothesis, this means the population variance is at least 17956. On the same level, you can conclude that the population standard deviation is at least 134.

I've made the test so that you have an example of how to do it.

I hope it helps!

step-by-step explanation:

i think something is missing in your question because y-1=(x-12) would not pass through the point (-4,-3). because if you replace x by -4 your are supposed to find y=-3 which is not the case her. if you replace x by -4 you find =-15.

i assume the right equation is y-1=1/4*(x-12) because this one is passing through both your points (if you are interested to know how i found that out i can tell you).

in this equation if i replace x by -4 i find y=-3 and if i replace x by 12, i find y=1 so the line representing this equation is passing through those 2 points.

then the standard form of the equation is finding an expression of y in function of x

y-1=1/4*(x-12)

y=x/4-3+1

y=x/4-2

hope that .

do you confirm there was a mistake in the question?

deez nu tz

step-by-step explanation: