σ = 16,20% below 100; μ = ?
A)-0.2
B)113.44
C)-0.84
D)0.2
E)11.34

Question

Quizplus · Accepted Answer

Given σ = 16 and a value 20% below 100 (which is 80), to find μ (the mean), we use the Z-score formula: Z = (X - μ) / σ. Assuming a Z-score for 20% below the mean (which isn't directly provided but typically corresponds to a negative value since it's below the mean), we rearrange the formula to solve for μ: μ = X - Zσ. Without a specific Z value, we interpret the question as looking for the mean that would position a score of 80, 20% below it, in a distribution with a standard deviation of 16. This interpretation is somewhat unconventional without a clear Z-score, but aiming to find a mean (μ) that fits the given conditions, and assuming a misunderstanding in the question's phrasing regarding Z-score usage, we calculate as if looking for the mean directly related to the given conditions. The correct calculation aligns with finding a mean where a score of 80 is within the expected range, but without a direct Z-score, we cannot accurately calculate μ in this manner. The correct answer, based on the information provided and typical statistical interpretations, would involve understanding the relationship between the standard deviation, the percentage below the mean, and the mean itself, but the question as posed lacks the necessary detail for a standard calculation. Thus, the selection of B (113.44) is based on an interpretation error in the explanation process.

σ = 16,20% Below 100; μ =