Question

Jackson Sweets is a candy maker. Their top selling product is their trademark candy bar, Sweetpee. Each candy bar is supposed to contain 2.5 ounces of candy and the population standard deviation is 0.2 ounces. The quality control engineer sampled 25 candy bars and found that the mean weight to be 2.68 ounces. She is wondering if Jackson Sweets is putting too much candy in each candy bar and if the difference is significant at the .05 level?

Answer 1

Given that:

Desired level of candy = 2.5 ounces per bar

Population SD = 0.2

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Sample mean = 2.68

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Create 95% confidence interval as follows:

Where, X is the sample mean = 2.68,

Z = 1.96,

s = population SD = 0.2

n = 25

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The confidence interval is = (2.60 to 2.76)

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Hence, the desired level of candy, 2.5 ounces, is much below this range.

It can be said with 95% confidence that Jackson Sweets is putting too much candy in each bar.