Question

Barbara and James are in two separate classes taught by Mrs. Oshinsky. In Barbara’s class, the mean grade on a poetry test is a 74 and the standard deviation is 8. In James’s class, the mean grade is a 79 and the standard deviation is 3. Barbara and James both earn a 92 on their tests.

(A) Which student performed better in comparison to his or her class? You must show calculations to justify your response, or no credit will be given.

(B) In James’s class, what grade is comparable to Barbara’s?

(C) In Barbara’s class, what grade is comparable to James’s?

(D) What is the 60th percentile grade for each of the two classes?

Is it possible if you could write down each equation used next to each step? Its helpful for me to see what is being used and why. Also is this type of question a binomial, geometric, hypergeometric, Poisson, normal, or a standard normal and how could I identify it in the future?

Answer 1

0 Solution Given data Barbara Jama Mean 9 Mean : 74 8 SD SD - Both earn 9a. 92-74 Z score of Barbara (ZB) = 8 9.25 Z score of James (Z;) = 92-79 3 4:33) - B We find Barbara in James class. XB - 79 2:25 3 XB = 0.25x3+79 85.751 X13 (6) we find James in Barbara dass X; - 74 4:33 8 4-33X3+14 х; xj Percentile ne find Goth e 108.641 grade for each two classs. 0.25315 Goth Percentile Zscore

for Barbara XB = x-74 0.25335 8 ::*: (0.25335*8) +74 Barbara class is :(76.03 for James 0.25335 X; - X-79 3 10.25335x3) +79 49.76 is 4 Jamy class