Consider the film speed data in Exercise 10-26. (a) Test H 0 : 2 1 =

Consider the film speed data in Exercise 10-26.

(a) Test H₀: σ²₁ = σ²₂ versus H₁: σ²₁ ≠ σ²₂ using α = 0.02.

(b) Suppose that one population standard deviation is 50% larger than the other. Is the sample size n₁ = n₂ = 8 adequate to detect this difference with high probability? Use α = 0.01 in answering this question.

Exercise 10-26

A photoconductor film is manufactured at a nominal thickness of 25 mils. The product engineer wishes to increase the mean speed of the film and believes that this can be achieved by reducing the thickness of the film to 20 mils. Eight samples of each film thickness are manufactured in a pilot production process, and the film speed (in microjoules per square inch) is measured. For the 25-mil film, the sample data result is x̅₁ = 1.15 and s₁ = 0.11, and for the 20-mil film the data yield x₂ = 1.06 and s₂ = 0.09. Note that an increase in film speed would lower the value of the observation in microjoules per square inch.