She had the fun data set of her class and she calculated the mean so that we do not have to remember the whole data set. Which sounds like a great idea but how do we know how many cookies to buy from the superstore. Let’s assume that we are preparing for the summer fair at our school and the headteacher suggested that we should have cookies for the whole school. It is a typical value in a given data set. Mean is the average of all the numbers (or observations) in a data set. These numbers are then later analysed using the mean, median, mode and range methods. The numbers that you collect for the data sets are called observations. In other words, you can say that we observed that Martha ate five cookies and Reshma ate three cookies.

In our fun data set example, the number of cookies that each pupil ate was the observation. Some times you may hear people talking about observations in a data set so let’s understand what it means. This is how our fun data set may look like, We know that some children can eat more than others but that is fine, we are simply interested in taking of note. For example, if we collect the data set of heights of pupils in a class then we can study it to find out what should be the size of the chairs and benches to sit on.įor fun, let’s imagine creating a dataset of how many cookies each pupil in a class can eat. We collect the data sets so we can analyse it and study it.

Why do we need a data set? How is it related to mean, median, mode? The postcodes of all houses in London with more than four family members would form another data set of families bigger than four. If we conduct a test and collect the scores of everyone who took the test then that would be a data set of scores. If we collect the height of every pupil in a class and write it down then we will call that as a data set of pupil’s height in a class.

2 Why do we need a data set? How is it related to mean, median, mode?Ī set of numbers (also called a data set) is a list of numbers in a data set that represents some common characteristics or relate to a particular topic or subject.

1 What is a set of numbers or data set?.

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