Determine if the outcome is unusual. Consider as unusual any result that differs from the mean by more than 2 standard deviations. That is, unusual values are either less than µ - 2? or greater than µ + 2?.
-The Acme Candy Company claims that 60% of the jawbreakers it produces weigh more than .4 ounces. Suppose that 800 jawbreakers are selected at random from the production lines. Would it be unusual for this sample of 800 to contain 423 jawbreakers that weigh more than .4 ounces?
A) Yes
B) No

Question

Quizplus · Accepted Answer

The expected number of jawbreakers weighing more than 0.4 ounces is 0.6 * 800 = 480. The standard deviation is sqrt(800 * 0.6 * 0.4) ≈ 13.86. The range for usual values is 480 ± 2 * 13.86, which is approximately 452.28 to 507.72. Since 423 is outside this range, it is unusual.

Determine If the Outcome Is Unusual