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Dvinal [7]
2 years ago
7

In 1990, the mean duration of long-distance telephone calls originating in one town was 7.2 minutes. A long-distance telephone c

ompany wants to perform a hypothesis test to determine whether the mean duration of long-distance phone calls has changed from the 1990 mean of 7.2 minutes. H0: μ < 7.2 minutes Ha: μ > 7.2 minutes H0: μ = 7.2 minutes Ha: μ ≠ 7.2 minutes H0: μ = 7.2 minutes Ha: μ ≤ 7.2 minutes H0: μ ≠ 7.2 minutes Ha: μ = 7.2 minutes
Mathematics
1 answer:
scoundrel [369]2 years ago
4 0

Answer:

We know that In 1990, the mean duration of long-distance telephone calls originating in one town was 7.2 minutes. And we want to test if the mean duration of long-distance phone calls has changed from the 1990 mean of 7.2 minutes (alternative hypothesis) and the complement rule would represent the null hypothesis.

The correct system of hypothesis are:

Null hypothesis: \mu =7.2

Alternative hypothesis: \mu \neq 7.2

So then the best option for this case would be:

H0: μ = 7.2 minutes Ha: μ ≠ 7.2 minutes

Step-by-step explanation:

We know that In 1990, the mean duration of long-distance telephone calls originating in one town was 7.2 minutes. And we want to test if the mean duration of long-distance phone calls has changed from the 1990 mean of 7.2 minutes (alternative hypothesis) and the complement rule would represent the null hypothesis.

The correct system of hypothesis are:

Null hypothesis: \mu =7.2

Alternative hypothesis: \mu \neq 7.2

So then the best option for this case would be:

H0: μ = 7.2 minutes Ha: μ ≠ 7.2 minutes

And in order to test the hypothesis we can use a one sample t test or z test depending if we know the population deviation or not

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