Question

he first step of a certain job application process is an exam. The exam is worth 100 points. The scores on the exam were normally distributed, with a mean score of 76 points and a standard deviation of 4.2 points. Last year, there were 440 applications. Of the 440 applicants, those with a minimum score of 68 points qualified to advance to the second step of the application process. The reference table lists z-scores and the associated cumulative probabilities.



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Approximately how many applicants advanced to the second step? Record your answer as a whole number.

Answer 1

z = (68 − 76) / 4.2 = −1.905.
P(score ≥ 68) = 1 − Φ(−1.905) ≈ 1 − 0.0286 = 0.9714.
Estimated number = 0.9714 × 440 ≈ 427.4 → 427 applicants.