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A labor rights group wants to determine the mean salary of app-based drivers. If she knows that the standard deviation is $1.1, how many drivers should she consider surveying to be 99% sure of knowing the mean will be within ±$0.79 ?

User Rohim Chou
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4 votes

Answer:

79 is the correct

Explanation:

he should consider surveying 79 app-based drivers to be 99% sure of knowing the mean salary within ±$0.71. The correct answer is 79.

To determine the sample size needed to estimate the mean with a given level of confidence, we can use the formula:

n = (Z * σ / E)^2

where:

n = sample size

Z = Z-score corresponding to the desired confidence level (99% confidence corresponds to Z = 2.576)

σ = standard deviation

E = margin of error

In this case, the margin of error is ±$0.71, so E = $0.71.

Substituting the given values into the formula:

n = (2.576 * 2.7 / 0.71)^2

n ≈ 79

Therefore, she should consider surveying 79 app-based drivers to be 99% sure of knowing the mean salary within ±$0.71. The correct answer is 79.

To learn more about mean visit;

User Don Hatch
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