Question

The following data set is from a survey of the weekly number of hours spent exercising for 40 high school students.

8	10	14	3	11	9	11	5	11	17
13	11	9	13	6	8	10	15	3	10
13	12	15	13	12	5	1	7	5	7
9	5	5	10	9	12	2	7	6	8

a) Put in order the data set and determine the mean, median and mode.

b) Calculate the bin width that will divide the data into 5 intervals. Show your calculations

c) Complete the frequency distribution table using the bin width calculated in question b)

Interval	Midpoint	Tally	Frequency	Relative Frequency	Cumulative Frequency

d) Produce a histogram of the data set.

e) Determine the mean interval, median interval and modal interval for grouped data.

f) Discuss the difference between the values for central tendency obtained for the ungrouped versus the grouped data set. In particular, compare the mode and the modal interval—which is a better measurement?

Answer 1

( a )

mean :

( b )

Bin width = ( max - min ) / # of intervals

=  ( 17 - 1 ) / 5

= 3.2

~ 3

( c )

( d )