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High school students across the nation compete in a financial capability challenge each year by taking a National Financial Capability Challenge Exam. Students who score in the top 14 percent are recognized publicly for their achievement by the Department of the Treasury. Assuming a normal distribution. How many standard deviations above the mean does a student have to score to be publicly recognized? (Round your answer to 2 decimal places.)

User Cybye
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1 Answer

4 votes

Answer:

The scores above 1.08 standard deviation from the mean are publicly recognized.

Explanation:

We are given the following information in the question:

Mean = μ

Standard Deviation = σ

We are given that the distribution of score is a bell shaped distribution that is a normal distribution.

Formula:


z_(score) = \displaystyle(x-\mu)/(\sigma)

We have to find the value of x such that the probability is 0.14


P( X > x) = P( z > \displaystyle(x - \mu)/(\sigma))=0.14


= 1 -P( z \leq \displaystyle(x - \mu)/(\sigma))=0.14


=P( z \leq \displaystyle(x - \mu)/(\sigma))=0.86

Calculation the value from standard normal z table, we have,


\displaystyle(x - \mu)/(\sigma) = 1.08\\\\x =\mu + 1.08\sigma

Thus, scores above 1.08 standard deviation from the mean are publicly recognized.

User RajeshM
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