What is a Line Plot?
A line plot is a graph that uses Xs or any icon to display the number of times a response has been recorded in a particular set of data. The Xs are generally placed along with the responses. Line plots are known as dot plots as well. Below is an example of a line plot based on a survey conducted by students.
The horizontal line measures the number of fruits students enjoy. For instance, to find out the number of students who enjoy 2 fruits a day, we will simply count the Xs above the number 2.
How to Make a Line Plot?
In order to prepare a line plot, we need to have a data set and plot that data on a number line accordingly. We put an X or any icon above each number in the data set. If a particular number appears more than once in the data, then we put extra Xs above that number. For example, the line plot for the data set 95, 95, 95, 95, 96, 96, 96, 97, 97, 98, 98, 99, and 99 will look like this:
Here, we have used dots instead of Xs to plot.
How to Interpret a Line Plot?
A line plot can be easily interpreted by looking at the Xs or dots plotted on the plot line and counting them accordingly. For example, from the above question, we can count the number of times 96 has appeared in the data set. 96 has appeared 3 times in the data set. Similarly, for other numbers, we can count the Xs and interpret the line plot.
How are Fractions Depicted on a Line Plot?
Fractions are used to show parts of a whole number. If we have to show \(\frac{3}{4}\) in a diagram, then it will look like this:
The shaded parts represent \(\frac{3}{4}\), as mentioned. Now, while representing fractions on a line plot, we will first look at fractions on a number line. We will represent \(\frac{3}{4}\) on a number line.
If you notice, the number line has been divided into 4 parts. As the fraction is a part of a whole number, we have depicted it along with the other parts of the whole number, 1. The number line begins from 0 and ends with 1 and represents the different parts of the whole number.
Solved Examples
1. From the following tally chart, prepare a line plot for the same data.
Answer: We have to prepare a line plot depending on the ages of the children. We will represent the ages on the horizontal axis and then plot the number of children for each age group.
2. Sam is planning to prepare a cake for his sister. He needs the following ingredients for the cake. Use the data from the following table to prepare a line plot.
Answer: Let us prepare a line plot based on the data given.
3. 10 people were surveyed on the amount of money they spend each day. Prepare a line plot based on the data.
Answer: Here, as we can see from the data, the denominators are different for some data. So, we have to write the data values as fractions with the same denominator. Here the denominators of the data set are 4 and 8. The LCM of 4 and 8 is 8, so let us change the denominator to 8 for all the fractions.
\(\frac{2}{4}=\frac{2 \times 2}{4 \times 2}=\frac{4}{8}\)
\(\frac{3}{4}=\frac{3 \times 2}{4 \times 2}=\frac{6}{8}\)
Now, we will prepare a number line that will represent the data values.
As you can see from the line plot, 1/8 is the most common data among others.
Line plots help display the frequency of data along the number line. It is a quick and easy way to analyze the data for a set of values. We can use it at our workplace to get prompt analysis of certain data.
Students are taught about bar graphs and pictographs from a very young age. Line plots create a stronger base for students by connecting the concepts of these two graphs together with more advanced concepts for higher classes.