Understanding Line Graph Construction

A line graph is a graphical representation of changes over a period of time. In a line graph, the horizontal axis is the x-axis, and the vertical axis is the y-axis. 

The x-axis usually has a time period throughout which we want to quantify the quantity of a certain entity or object on the y-axis. 

You can use a line graph to see if the quantity on the y-axis is increasing or decreasing over time. 

A line graph depicts whether a trend is rising or falling.

How to Draw a Line Graph:

A line graph can be made using the techniques below.

Create a table:

On a paper, draw the x- and y-axes. Place a title at the top of the page that briefly summarises the chart’s purpose.

Each axis should be labelled as follows:

If one of the elements is time, it should be plotted on the horizontal (x) axis. The other numerical values, or dependent variables, should be shown on the vertical (y) axis.

The name of the numeric system as well as the measurements employed should be labelled on each axis. For instance, you may label the x-axis with independent variables such as hours or months, indicating that each number on the axis represents the amount of hours or months. Divide each axis into appropriate increments evenly.

Data is commonly presented in a two-column table corresponding to the x- and y-axes for a line graph. Your line graph will immediately reflect the values once you’ve added your data.

Make a key: If you’re comparing several items, make a key that distinguishes each line by its colour.

Important Line Graph Notes:

Here are some important things to know while making a line graph.

Select the title that best describes the material.

Take variable values in simple terms to make them easier to comprehend.

Avoid drawing too many lines across the graph. To make comparisons easier, the maximum number of lines should be four.

Questions:

1) What is the ratio of firm B’s income in 1996 to company A’s income in 1993?

A. 9: 10

B. 10: 9

C. 3: 2

D. 15: 13

Solution:

In 1996, Company B earned 60 lakhs. In 1993,firm A earned 40 lakhs. 

60/40 = 3:2 is the required ratio.

2)If company B’s expenditure in 1997 was Rs. 50 lakhs, and the percent profit made by both companies A and B in 1997 was equal, what was company A’s profit in 1997 (approximately)?

A.5 lakhs rupees.

B. 4.5 lakhs rupees.

C.5.5 lakhs rupees.

D.6.2 lakhs rupees.

Solution:

In 1997, firm B earned 55 lakh dollars. In 1997, firm B spent 50 lakh .10% profit.

Expenditure = 60 / 1.1 = 54.5

 ⇒ amount of profit

 ⇒ 60 – 54.5 = 5.5 lakh.

3)If firm ‘B’ had a 25% profit in 1995, what was it’s approximate expenditure in 1995?

A.22 lakhs rupees

B. 29 lakhs rupees

C.40 lakhs rupees

D. 27 lakhs rupees

Solution

For company ‘B’ profit = 25%. Income of company B = 50 lakh in 1995

Required expenditure = 50 / 1.25 = 40 lakh

4)What is the annual average income of company ‘B’ as a percentage of the annual average income of company ‘A’?

(approximately)

A.70 percent 

B.110 percent 

C.113 percent 

D.90 percent.

Solution:

Company A’s average income = (25 + 40 + 35 + 45 + 50 + 60 + 55) / 7 = 44.285

Company B’s average income = (40 + 35 + 45 + 50 + 60 + 55 + 65) / 7 = 50

Required percentage age = 50 / 44.285 x 100 = 112.9 % =113 %

5)What percentage of firm ‘A’s’ income in 1996 is equal to company ‘B’s’ income in 1992?

A.75 percent 

B.63.64 percent 

C.133.33 percent 

D.125 percent 

Solution

In 1992, firm B earned 40lakh.

In 1992, firm B earned 40lakh. In 1996, firm A earned 50 lakh.

And 50 lakh is 125% of 40 lakh.

Tips to quickly solve line graphs in data interpretation section:

1. The ability to understand data, extrapolate it into a mathematical solution, and then potentially use that solution to make a judgement is the skill.

2. Begin by scanning the information and data. What’s the name of the book? What do the axes and keys represent? Make a mental note of whether objects are numbers, years, or other forms of data, but don’t spend too much time thinking about useless information.

3. Then read the question thoroughly to determine which exact data is necessary (e.g. March and April, not any other months).

4. Being quick with approximations and calculations is essential for excelling in Line Graph questions.

5. Online Questions Graphs appear frequently in practically all competitive tests; therefore, the more you prepare, the better.

Tables, bar graphs, line graphs, paragraphs, and pie charts are just a few examples of how data can be represented.A line graph is a statistical tool for analysing the trend of data that changes in a coordinate plane over a specific time interval.

An x-and-y-axis is used to depict time and data. It’s also known as a line graph. The time is normally on the x-axis, or horizontal axis, while the data that varies with regard to time is on the vertical axis, or y-axis. A ‘data point’ is a unit of measurement for every interval of time. A little circle is used to represent it.