he mean height of a certain kind of plant is 190 centimeters. Suppose we want to carry out a hypothesis test to see if the mean height when these plants are treated with a certain chemical differs from 190 . State the null hypothesis and the alternative hypothesis that we would use for this test.
Ho: mean = 190
Ha: mean ≠ 190
To state the null hypothesis (H0) and the alternative hypothesis (H1) for this hypothesis test, we need to consider the purpose of the test.
In this case, we want to determine if the mean height of the plants when treated with a certain chemical differs from 190 centimeters.
The null hypothesis (H0) assumes that there is no difference in the mean height:
H0: The mean height of the plants when treated with the chemical is equal to 190 centimeters.
The alternative hypothesis (H1) assumes that there is a difference in the mean height:
H1: The mean height of the plants when treated with the chemical is not equal to 190 centimeters.
Note that the alternative hypothesis is two-tailed because we are considering the possibility that the mean height could be either higher or lower than 190 centimeters.