A Farmer Uses a Lot of Fertilizer to Grow His

question 27

Multiple Choice

A farmer uses a lot of fertilizer to grow his crops. The farmer's manager thinks fertilizer products from distributor A contain more of the nitrogen that his plants need than distributor B's fertilizer does. He takes two independent samples of four batches of fertilizer from each distributor and measures the amount of nitrogen in each batch. Fertilizer from distributor A contained 23 pounds per batch and fertilizer from distributor B contained 18 pounds per batch. Suppose the population standard deviation for distributor A and distributor B is four pounds per batch and five pounds per batch, respectively. Assume the distribution of nitrogen in fertilizer is normally distributed. Let µ₁ and µ₂ represent the average amount of nitrogen per batch for fertilizer's A and B, respectively. Which of the following is the correct value of the test statistic?

• A) t₆ = −1.5617
• B) t₆ = 1.5617
• C) z = −1.5617
• D) z = 1.5617

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Definitions:

Break-even Point

The juncture where the sum of all expenses matches the sum of all income, leading to neither a profit nor a deficit.

Variable Expense

Expenses that vary directly with the amount of production or the degree of operational activity.

Contribution Margin Ratio

The percentage of each sale that exceeds the variable costs of production.

Break-even Point

The level of production or sales at which total revenues equal total expenses, resulting in neither profit nor loss.