Grade Six Mathematics
Hello Boys and Girls! welcome to this week’s session. In our previous session, we concluded our exploration of consumer arithmetic. In this week’s column, we will delve into the principles behind tally charts and pictographs.
Let’s begin.
Tally Chart
Have you come across the term “Tally” before? Have you engaged in tallying during a previous grade? If so, we’ll draw upon your past experience to explore today’s topic! If not, that’s perfectly fine; our aim here is to learn something new each week!
What is a tally chart?
A tally chart is a simple way of recording data and counting the amount of something (frequency). This involves gathering the data, organizing it into categories, and then marking tallies to calculate frequencies.
Point to note:
Tallying has one vertical line which is made for each of the first four numbers and the fifth number is represented by a diagonal line across the previous four. The chart below contains tally marks for the numbers counting from 1 to 10.
Frequency and Frequency Tables
The frequency of a particular data value is the number of times the data value occurs.For example, if three students have a score of 50 in mathematics, then the score of 50 is said to have a frequency of 3. The frequency of a data value is often represented by f.
A frequency table is constructed by arranging collected data values in ascending order of magnitude with their corresponding frequencies.
Example 1
Let’s say we wanted to collect some data on the ways of transport used by students to get to school. We would start collecting data and writing the answers in a list.
The best way to sort this data set is to use tally charts.
The data collection looks like this:
walk, bus, bike, walk, bike, bus, walk, car, walk, bike, bike, bus, walk, walk, walk, car, bus, walk, bus, bus, walk, car, car, walk, walk, train, bike, bus, walk, walk
The tally chart for the same data will look like this:
It’s that simple!
Ok boys and girls, it’s your time now to apply the knowledge you have learned so far!
Read the instruction carefully.
Exercise 1
Complete the tally and frequency table below:
Great job, students!
Here’s another exercise for you to complete:
Exercise 2 (i) How many students scored 10 marks? (ii) How many students scored above 10 marks? (iii) How many students wrote the test?
Excellent work, boys and girls!
Let’s now examine how data can be represented on a special chart called the pictograph.
Pictograph
What is a pictograph?
A pictograph is a pictorial representation of numerical data using images, icons, or symbols. In other words, it is a chart that uses drawings or pictures to display statistical data.
Let us examine an example:
Example 1
The chart below shows the number of red-colored boxes sold by William, a shopkeeper, six days a week. Use the pictograph to answer the questions.