Question

During the Middle Ages, armies often used catapults to launch flaming projectiles at their enemies. Because of the inferior materials and manufacturing processes of the time, excessive variability in the weight of flaming projectiles could damage the arm of a catapult, thus leading to inaccurate launches. Because of this problem, most armies maintained a staff of quality engineers to inspect projectiles prior to their use. During the Hundred Years’ War, the English army applied the following hypothesis test to each shipment of projectiles they received.

They used a level of significance of 0.05 and a sample of size 25. Suppose for one particular shipment the test statistics was 30.

What is the P-value for the test?

Answer 1

In this

n=25

degree of freedom (dF)= 25-1 = 24

Test statistic $\chi ^{2}$ = 30

P value = P($\chi ^{2}$ > 30) with df=24 =0.1848