In a statistic class, 10 scores were randomly selected with the following results were obtained:
74, 73, 77, 77, 71, 68, 65, 77, 67, 66

-What is the 90^th percentile?

Question

In a statistic class, 10 scores were randomly selected with the following results were obtained: 74, 73, 77, 77, 71, 68, 65, 77, 67, 66 -What is the 90^th percentile? A)77 B)73 C)74 D)67 E)65.9

Quizplus · Accepted Answer

To find the 90th percentile in a data set, first, the data must be ordered from least to greatest. The given data in order is: 65, 66, 67, 68, 71, 73, 74, 77, 77, 77. The formula to find the kth percentile is P = (k/100)(n+1), where P is the position in the data set, k is the desired percentile, and n is the number of data points. For the 90th percentile, P = (90/100)(10+1) = 9.9. Since we can't have a fractional position, we round up to the nearest whole number, which is 10 in this case. The 10th value in the ordered data set is 77, making 77 the 90th percentile.

In a Statistic Class, 10 Scores Were Randomly Selected with the Following