Question

18 ) Five numbers are given: (5, 10, 15, 5, 15). Now, what would be the sum of deviations of individual data points from their mean?

A) 10

B)25

C) 50

D) 0

E) None of the above

12) The following data values represent the number of work hours per week for a sample of college students during the previous spring semester.

30, 17, 16, 20, 14, 28, 18, 17, 29, 14, 20, 29, 36, 69, 16, 20, 27, 71, 10, 16

Using the modified box plot function, state the value of any outliers , if any exists, and compute the Inter-Quartile Range (IQR).

	a.	10 is the only outlier and IQR = 12.5
	b.	10 and 71 are the only outliers and IQR = 12.5
	c.	71 is the only outlier and IQR = 13
	d.	69 and 71 are the only outliers and IQR = 13
	e.	There are outliers and IQR = 13

Answer 1

18)

since sum of deviation of individual data points from their mean =0

option D is correct

12)

putting above in ascending order:

x
10
14
14
16
16
16
17
17
18
20
20
20
27
28
29
29
30
36
69
71

Quartile 1 =middle value in lower half =16

Quartile 3 =middle value in upper half =29

IQR =Q3-Q1 =29-16=13

lower fence =Q1-1.5*IQR =16-1.5*13 =-3.5

upper fence =Q1+1.5*IQR =16+1.5*13 =48.5

since 69 and 71 falls outside the fence values

Correct option is d:

69 and 71 are the only outliers and IQR = 13