Two processes are used to produce forgings used in an aircraft wing assembly. Of 200 forgings selected from process 1, 10 do not conform to the strength specifications, whereas of 300 forgings selected from process 2, 20 are nonconforming. a) Esetimate the fraction nonconforming for each process. b) Test the hypothesis that the two process have identical fractions nonconforming. Use alpha =0.05. c) Construct a 90% confidence interval on the difference in fraction nonconforming between the two processes.

a.

b-Check illustration  below

c.(-0.0517,0.0177

Step-by-step explanation:

a.let denote processes 1 & 2.

For : T1=10,n1=200

For :T2=20,n2=300

Therefore

b. To test for hypothesis:-

i.

ii.For a two sample Proportion test

iii. for (0.5 alpha IS 0.025),

reject if

iv. Do not reject . The noncomforting proportions are not significantly different as calculated below:

z=-0.78

c. for the p1-p2 is given as:

=(-0.0517,+0.0177)

*CI contains o, which implies that proportions are NOT significantly different.

1) is right

step-by-step explanation: