- #1
superwolf
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If the average number of raisins in a randomly chosen bun is 9 with a variance of 9, how many buns must be tested if a test with a significance level of 0.05 with 90% probability is going to reveal than the number of raisins is less than 10?
ATTEMPT:
<br /> n = \frac{(z_{\alpha} + z_{\beta})^2 \sigma^2}{\delta^2} = \frac{(1.645+1.28)^2 \cdot 9}{1^2} = 77.0006
So, at least 78 buns.
Correct answer. At least 82 buns.
What's wrong?
ATTEMPT:
<br /> n = \frac{(z_{\alpha} + z_{\beta})^2 \sigma^2}{\delta^2} = \frac{(1.645+1.28)^2 \cdot 9}{1^2} = 77.0006
So, at least 78 buns.
Correct answer. At least 82 buns.
What's wrong?
