Everything Maths Grade 10

Worked example 2: Qualitative and quantitative data

QUESTION

Thembisile would like to know who the most popular cellular provider is among learners in his school. This

time Thembisile randomly selects 20 learners from the entire school and asks them which cellular provider

they currently use. The results were:

Cell C Vodacom Vodacom MTN Vodacom

MTN MTN Virgin Mobile Cell C 8-ta

Vodacom MTN Vodacom Vodacom MTN

Vodacom Vodacom Vodacom Virgin Mobile MTN

Is this data set qualitative or quantitative? Explain your answer.

SOLUTION

Since each response is not a number, but one of a small number of possibilities, these are categorical qualitative

data.

Exercise 10 – 1:

1.The following data set of dreams that learners have was collected from Grade 12 learners just after their

final exams:f”I want to build a bridge!”; ”I want to help the sick.”; ”I want running water!”g

Categorise the data set.

2.Categorise the following data set of sweets in a packet that was collected from visitors to a sweet shop.

f23; 25; 22; 26; 27; 25; 21; 28g

3.Categorise the following data set of questions answered correctly that was collected from a class of maths

learners.

f3; 5; 2; 6; 7; 5; 1; 2g

For more exercises, visit http://www.everythingmaths.co.za and click on ’Practise Maths’.

1.2GM2 2.2GM3 3.2GM4

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10.2 Measures of central tendency EMA6Y

Mean EMA6Z

DEFINITION: Mean

The mean is the sum of a set of values, divided by the number of values in the set. The notation for the mean

of a set of values is a horizontal bar over the variable used to represent the set, for examplex. The formula for

the mean of a data setfx 1 ;x 2 ;:::;xngis:

x=

1

n

∑n

i=1

xi

=

x 1 +x 2 +: : :+xn

n

358 10.2. Measures of central tendency