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Doctoral Student Salaries Full-time Ph.D. students receive an average of $12,837 per year. If the average salaries are normally distributed with a standard deviation of $1500, find these probabilities. Round the final answers to at least four decimal places and intermediate z-value calculations to two decimal places

User WuTangTan
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Final answer:

The question asks for the probabilities of certain salaries for full-time Ph.D. students, using the normal distribution and standard deviation. Calculating z-scores allows for finding these probabilities by referencing the standard normal distribution tables or using a calculator.

Step-by-step explanation:

The question involves finding probabilities from a normally distributed set of data, which in this case is the full-time Ph.D. student salaries. Given the average salary of $12,837 and a standard deviation of $1500, one can use z-scores to calculate various probabilities regarding the salaries. For example, the probability of a salary being above a certain amount, or between two amounts, can be computed by converting those salary amounts into z-scores and using the standard normal distribution tables.

To find a probability for a specific salary range using the z-score formula: z = (X - μ) / σ, where X is the salary of interest, μ is the mean salary, and σ is the standard deviation. Once the z-score is found, the standard normal distribution table or a calculator can be used to find the corresponding probability. Understanding the concept of normal distribution and z-scores is imperative for these calculations, especially for students involved in fields like statistics, economics, and other sciences that often deal with data analysis and interpretation.

User ZAfLu
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