An agronomist believes that a newly developed plant food will increase the mean yield of tomato plants. 29 randomly selected plants were treated with the new plant food and they had a mean yield of 28.4 pounds and a standard deviation 2.8 pounds. The true mean yield of tomato plants without the newly developed plant food is 26.5 pounds. If we assume that yield from a tomato plant is normally distributed, test at the 0.05 level to determine if the new plant food increases the mean yield of tomato plants. Be sure to state and check assumptions. Perform the test even if you conclude the assumptions are not met. Construct and interpret a 95% confidence interval for the true mean yield from the tomato plants on the newly developed plant food.
Added by Melissa A.
Step 1
The null hypothesis (H0) is that the new plant food does not increase the mean yield of tomato plants. The alternative hypothesis (Ha) is that the new plant food does increase the mean yield of tomato plants. H0: μ = 26.5 Ha: μ > 26.5 Step 2: Check assumptions. Show more…
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