Question

The plant-breeding department at a major university developed a new hybrid boysenberry plant called Stumptown Berry. Based on research data, the claim is made that from the time shoots are planted 90 days on average are required to obtain the first berry. A corporation that is interested in marketing the product tests 60 shoots by planting them and recording the number of days before each plant produces its first berry. The corporation wants to know if the mean number of days is different from the 90 days claimed.

A random sample was taken and the following test statistic was z = -2.15 and critical values of z = ±1.96 was found.

What is the correct decision and summary?

• A.

  Reject H₀ , there is enough evidence to support the corporation's claim that the mean number of days until a berry is produced is different from 90 days claimed by the university.

• B.

  Reject H₁ , there is not enough evidence to reject the corporation's claim that the mean number of days until a berry is produced is different from 90 days claimed by the university.

• C.

  Accept H₀ , there is enough evidence to support the corporation's claim that the mean number of days until a berry is produced is different from 90 days claimed by the university.

• D.

  Reject H₀ , there is not enough evidence to support the corporation's claim that the mean number of days until a berry is produced is different from 90 days claimed by the university.

• E.

  Do not reject H₀, there is not enough evidence to support the corporation's claim that the mean number of days until a berry is produced is different from 90 days claimed by the university.

Answer 1

Solution:

Given data

Test statistic, z = -2.15

critical values of z = ± 1.96

We have to find the correct decision and summary:

Critical values of z >  Test statistic, z

± 1.96 > - 2.15

Since the critical values of Z is greater than Test statistic, z. Therefore we do not reject the null hypothesis(H0)

Answer:

Do not reject H0, there is not enough evidence to support the corporation's claim that the mean number of days until a berry is produced is different from 90 days claimed by the university.

Hence the "Option - E" is the correct answer.