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, o = ₂ = 3

cm/s. From a random sample of size n₁ = 20

and n₂ = 20, we obtain ₁ = 18.02 cm/s and

x₂ = 24.32 cm/s.

Statistical Tables and Charts

(a) Test the hypothesis that both

propellants have the same mean burning

rate. Use a fixed-level test with a = 0.05

and choose the appropriate conclusion

from below:

Since

,we

the null hypothesis.