Easy question but i'm being stupid somewhere. quite frustrating... enough to post it :surprise:(adsbygoogle = window.adsbygoogle || []).push({});

Basically the question is

Semiconductor wafer testing:

365 dies, 201 passed probing.

Assuming stable process calculate a 95% confidence interval for the proportion of all dies that pass the probe.

So x_bar = 201/365

std_dev = p*(1-p) = .228

n=356.

the answer in the book is .513,.615 and i'm not getting that. same for the next question and the one after lol.

:yuck: :yuck:

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# Confidence Intervals (easy question)

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