Statistics · FRQ Trainer

A researcher tests whether a new fertilizer increases mean tomato yield. She randomly assigns 40 plants to two groups of 20. New: x̄₁ = 5.4 kg, s₁ = 1.2. Standard: x̄₂ = 4.7 kg, s₂ = 1.1. (a) State the hypotheses. (b) Name the test and check conditions. (c) The test gives t = 1.92, df ≈ 37, p = 0.031. State a conclusion at α = 0.05 in context. (d) Explain what a Type I error would be here.