Question

The burning rates of two different solid-fuel propellants used in aircrew escape systems are being studied. It is known that both propellants have approximately the same standard deviation of burning rate; that is, σ1=σ2=3 cm/s. From a random sample of size n1=20 and n2=20, we obtain x¯1=18.02 cm/s and x¯2=24.35 cm/s.

(a) Test the hypothesis that both propellants have the same mean burning rate. Use a fixed-level test with α=0.05 and choose the appropriate conclusion from below:

Since Choose your answer; Since  -6.67 < -1.96. or -6.67 < 1.96, we _ the null hypothesis

(b) What is the P-value of the test in part (a)? Round your answer to 3 decimal places (e.g. 98.765).   

(c) What is the β-error of the test in part (a) if the true difference in mean burning rate is 2.5 cm/s?

(D)Construct a 95% confidence interval on the difference in means μ1-μ2.

Round your answers to 3 decimal places (e.g. 98.765).

Answer 1