The mean height of coastal redwood trees is known to be 200 feet. In order to test whether a community of coastal trees were gro

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3 years ago

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The mean height of coastal redwood trees is known to be 200 feet. In order to test whether a community of coastal trees were gro

wing to be healthy in a park with high rates of tourism, a random sample of 20 trees were measured. It was found that for the 20 sampled trees, the average height was 197.5 feet with a standard deviation of 6.7. It is known that tree heights follow a normal distribution
The mean height of coastal redwood trees is known to be 200 feet. In order to test whether a community of coastal trees were growing to be healthy in a park with high rates of tourism, a random sample of 20 trees were measured. It was found that for the 20 sampled trees, the average height was 197.5 feet. It is known that tree heights follow a normal distribution with a standard deviation of 7.

Which of the following is correct:

In the first scenario, the standard deviation is calculated from the sample, therefore a z-test should be used.

In the first scenario, the population standard deviation is known, therefore a z-test should be used.

In the first scenario, the population standard deviation is known, therefore a t-test should be used.

In the first scenario, the standard deviation is calculated from the sample, therefore a t-test should be used.

Mathematics

1 answer:

blagie [28] · Answer 1 · 2022-08-25T20:37:19+03:00

Answer:

Answer is simple:

Step-by-step explanation:

Solve this: The mean height of coastal redwood trees is known to be 200 feet. In order to test whether a community of coastal trees were growing to be healthy in a park with high rates of tourism, a random sample of 20 trees were measured. It was found that for the 20 sampled trees, the average height was 197.5 feet with a standard deviation of 6.7. It is known that tree heights follow a normal distribution

The mean height of coastal redwood trees is known to be 200 feet. In order to test whether a community of coastal trees were growing to be healthy in a park with high rates of tourism, a random sample of 20 trees were measured. It was found that for the 20 sampled trees, the average height was 197.5 feet. It is known that tree heights follow a normal distribution with a standard deviation of 7.

Which of the following is correct:

In the first scenario, the standard deviation is calculated from the sample, therefore a z-test should be used.

DUH