DSC2602 - EXAM PACK (2022)

DSC2602
EXAM PACK




Assignment Solutions
Questions. Answers

,DSC2602
EXAM PACK




Assignment Solutions
Questions. Answers

, DSC2602: 2021
SOLUTIONS TO ASSIGNMENT 04

PLEASE NOTE:
• The solutions to all written assignments will only be published on myUnisa under Additional
Resources.
• The solutions given below are only model answers, using the content from Lessons 1 to 3.
There might also be other ways to arrive at the same correct answer.
• This assignment contributes 25% towards your semester mark.




1

, Question 1

QUESTION:
The following frequency distribution table represents the ages of 100 employees of a certain
company:
Age interval Frequency
20 – 29 30
30 – 39 35
40 – 49 20
50 – 59 10
60 – 69 5



1.1 Identify the modal interval for the data set. (1)

1.2 Determine the median interval for the data set. (2)

1.3 Calculate the mean for the data set. (4)

1.4 Calculate the variance for the data set to two decimal places. (3)


[10]


MODEL ANSWER:
1.1 The modal interval is the interval in the data set with the highest frequency. For the
given data set, the 30 – 39 interval has the highest frequency of 35. Therefore, the modal
interval is the [30 – 39] interval.
1.2 To determine the median interval, we find the interval which contains the middle value
of the ordered data set. The median is the
n+1 100 + 1
= = 50,5-th value.
2 2
To identify the 50,5-th value, the cumulative frequency of the data set is shown in the
table below:
Age interval Frequency Cumulative frequency
20 – 29 30 30
30 – 39 35 65
40 – 49 20 85
50 – 59 10 95
60 – 69 5 100


Using the cumulative frequency, we find that the median value falls in the 30 – 39 interval.
Therefore, the median interval is the interval [30 – 39].

2