Question

The following data represent the hemoglobin (in g/dL) for 20 randomly selected cats.

10.0 10.3 5.7 8.9 7.8 10.6 13.4 8.7 9.5 11.2

12.9 11.7 7.7 10.3 10.7 9.4 9.6 13.0 9.9 12.5

a) Compute the sample mean.

b) Find the Median.

c) Compute the range.

d) Compute the sample variance

e) Compute the sample standard deviation.

Answer 1

a)

Sample mean = X / n

= 203.8 / 20

= 10.19

b)

Write data in ascending order.

5.7, 7.7, 7.8, 8.7, 8.9, 9.4, 9.5, 9.6, 9.9, 10, 10.3, 10.3, 10.6, 10.7, 11.2, 11.7, 12.5, 12.9, 13, 13.4

median = ( n + 1 ) / 2 th observation

= ( 20 + 1) / 2

= 10.5th oservation

= 10.15

c)

Range = Highest value - Lowest value

= 13.4 - 5.7

= 7.7

d)

Sample variance = ( X2 - n 2 ) / n - 1

= ( 2148.88 - 20 * 10.192 ) / 19

= 3.7978

e)

Sample standard deviation = sqrt [ sample variance ]

= sqrt [ 3.7978 ]

= 1.9488