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a computer software company would like to estimate how long it will take a beginner to become proficient at creating a graph using their new spreadsheet package. past experience has indicated that the time required for a beginner to become proficient with a particular function of the new software product has an approximately normal distribution with a standard deviation of 24 minutes. find the sample size necessary to estimate the true average time required for a beginner to become proficient at creating a graph with the new spreadsheet package to within 6 minutes with 99% confidence.

User DPS
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Final answer:

To estimate the average time required for a beginner to become proficient with a new software function to within 6 minutes at a 99% confidence level, a sample size of 174 is required, given a known standard deviation of 24 minutes.

Step-by-step explanation:

The problem involves determining the sample size necessary for a computer software company to estimate the average time it takes for a beginner to become proficient at creating a graph using their spreadsheet package with a given level of confidence and margin of error.

The known standard deviation (σ) of the past experiences is 24 minutes, and the desired margin of error (E) is 6 minutes.

To obtain this estimate within a 99% confidence interval, we use the z-score associated with a 99% confidence level, which is approximately 2.576.

The formula for finding the sample size (n) when the population standard deviation is known is:

n = (z * σ / E)^2

Plugging in the values we get:

n = (2.576 * 24 / 6)^2

n ≈ 173.29

Since we cannot have a fraction of a sample, we round up to the nearest whole number. Therefore, the required sample size is 174.

User Peter Keller
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Answer: According to the information provided, we can solve the question as follows: It is given that,Confidence level is 0.95, B=3, and standard deviation is 16. We employ the z distribution to calculate the samplesize for a population with a known standard deviation. The two-tailed z* value at the 0.03 level of significance is 1.94. We compute the necessary sample size as stated below by substituting these numbers in the formula that follows:Hence, the answer is 107

Step-by-step explanation:

User XSYS
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