Grades in large classes are sometimes approximately normally distributed—a fact that serves as the justification for "grading on a bell curve." a common practice for very large classes is to give 16% of students a grades, 34% b grades, 34% c grades, and 16% d and f grades. assuming a normal distribution of grades, what are the z-scores for these letter grades?

Grade A:

Grade B:

Grade C:

Grade D:

Step-by-step explanation:

Problems of normally distributed samples can be solved using the Z score table.

The Z score of a measure represents how many standard deviations it is above or below the mean of all the measures.

Each Z score has a pvalue. This represents the percentile of the measure.

In this problem, we have that:

The upper 16% of the class get A grades. The upper 16% has a pvalue of at least 100% = 16% = 84% = 0.84. This is .

The middle 34% of the class get B grades. The middle 34% has a pvalue of at least 84%-35% = 50% = 0.5 and at most 0.84. This is .

Those between a pvalue of 0.5-0.34 = 0.16 and 0.5 get get grade C. has a pvalue of 0.16. So a grade C is in the interval .

Those with Z lesser than -1 get grades D and F

0.85 or 85%

step-by-step explanation:

1) divide 23 by 27

2) round the decimal to the nearest 10

3) so your answer would be 0.85 or 85%

the answer is d. (1.2, -4.7) on edgn

hope this !