A professor would like to assign grades such that 7% of students receive Fs. If the exam average is 62 with a standard deviation of 13, what grade should be the cutoff for an F? (Round your answer.)
A) 43
B) 49
C) 50
D) 55

Question

Quizplus · Accepted Answer

The cutoff for an F, which is given to the lowest 7% of students, corresponds to a Z-score in a normal distribution. The Z-score for 7% (or the 7th percentile) is approximately -1.5. Using the Z-score formula Z = (X - μ) / σ, where X is the score, μ is the mean (62), and σ is the standard deviation (13), we can solve for X: -1.5 = (X - 62) / 13. Solving for X gives X ≈ 43. Therefore, the cutoff grade for an F should be around 43.

A Professor Would Like to Assign Grades Such That 7