Question

1.) Find the mean, the median, and the mode for the number of vehicles owned in a survey of 52

households.

x	0	1	2	3	4	5	6	7
f	2	12	15	11	6	3	1	2

2.) Find the range, the variance, and the standard deviation for the sample represented by the data frequency table.

x	-1	0	1	4
f	1	1	3	1

3.) A random sample of 49 invoices for repairs at an automotive body shop is taken. The data are arrayed in the stem and leaf diagram shown. (Stems are thousands of dollars, leaves are hundreds, so that for example the largest observation is 3,800.)

3	5	6	8
3	0	0	1	1	2	4
2	5	6	6	7	7	8	8	9	9
2	0	0	0	0	1	2	2	4
1	5	5	5	6	6	7	7	7	8	8	9
1	0	0	1	3	4	4	4
0	5	6	8	8
0	4

For these data, Σx=101,100, Σx^2=244,830,000

a. Compute the mean, median, and mode.

b.Compute the range.

c. Compute the sample standard deviation.

4.Consider the data set represented by the ordered stem and leaf diagram

10	0	0
9	1	1	1	1	2	3
8	0	1	1	2	2	3	4	5	7	8	8	9
7	0	0	0	1	1	2	4	4	5	6	6	6	7	7	7	8	8	9
6	0	1	2	2	2	3	4	4	5	7	7	7	7	8	8
5	0	2	3	3	4	4	6	7	7	8	9
4	2	5	6	8	8
3	9	9

a. Find the percentile rank of the grade 75.

b. Find the percentile rank of the grade 57.

5.) Find the five-number summary and the IQR and sketch the box plot for the sample represented by the

data frequency table.

x	-5	-3	-2	-1	0	1	3	4	5
f	2	1	3	2	4	1	1	2	1

Answer 1

1)

MEAN= 2.58

Median:Here 1/2*N= 1/2*52= 26

Cumulative frequency (C.F) just greater than 30 is 40 Thus median is 3

Mode: Value of x corresponding to the maximum frequency that is 15 is 2 . Hence Mode is 2.

NOTE: As per rule we are allowed to solve first question. I have done it with explanation. Please repost rest questions.