Question

1. The heart rates (beats per minute) of 20 people are as follows:

60 60 65 66 66 67 70 72 75 76 76 77 80 80 81 82 82 84 85 86.

(a) Calculate the percentile rank for a person with a score of 80.

(b) What does the percentile rank from (b) mean?

Answer 1

The given data is:

60,60,65,66,66,67,70,72,75,76,76,77,80,80,81,82,82,84,85,86

a)

we ant to find percentile rank for a person with a score of 80.

Percentile rank = [ ( M + ( 0.5 * R ) ) / Y ) ] * 100

Where,

M = numbers less than 80

Y = total numbers

R = number of times 80 appears

Percentile rank = [ ( 12 + ( 0.5 * 2) ) / 20 ] *100

Percentile rank = 65

b)

Percentile rank in part a mean:

65% of the numbers in the data set are less than or equal to 80.