Formulas for Spider Web Chart

Formulas to solve Spider Web Charts questions

Definition & Formula

A Spider Web Chart, also called as Radar Chart, Spider Chart or Web Chart, is a graphical method of displaying multivariate data in the form of a two-dimensional chart of three or more quantitative variables represented on axes starting from the same point.

Importance of Spider Web Charts :

  • They provide a very easy way to see if someone is competent or not.
  • They are great input in the development of learning plans.




In the question below, the sales of TV and laptop in the subsequent years from 2004 to 2009 is given. The figures given to you is in million. Based on the figure answer the questions below.


Question 1 .

 How many times do the sales of a laptop less than the TV in the given years?

A. One             

B. Two             

C. Three         

D. Four


Ans: Here the sales of televisions and laptops of six different years are given. You need to see that in which year the sale of TV was greater than the sale of the laptop. The values of different sales of units are given to you in the radar diagram above.

From the figure you can see that sales of the laptops in 2004 were lower than the sales TVs in 2004, similarly, sales of a laptop in 2005, 2008, and 2009 was lower than the sale of TVs in that year. So, there are four years where the sale of the laptop was lower than the sale of TV. Thus, the correct answer is D.


Question 2.

 Find the ratio of the total number of televisions sold to the total number of laptops sold in all these years.

A. 4: 5         

B. 5: 6           

C. 5: 4           

D. 6: 5


Ans: Here, you only have to add the total number of televisions laptop sold in all these years and compare them to find the ratio. The total number of televisions sold from 2004 to 2009 are 25 + 22.5 + 22.5 + 25 + 25 + 30 = 150. And the total number of laptops sold are: 20 + 15 + 25 .5 + 30 + 20 + 10 = 120.5. Thus the ratio of the is 150: 120.5 = 5: 4. So, the correct answer is C.


Question 3.

Which item and for which year shows the highest percentage increase in the sales in the previous year?

A. Laptop 2007                         

B. TV 2007

C. Laptop 2006                         

D. TV 2009


Ans: In this question, we need to find the increase in the percentage of the given items in comparison to previous years. Instead of checking all the years, we will only check percentage increase for the one given in the option. For laptop 2007, in the previous year, the sales were 30 million while in 2006 it was 25.5 so there is an increase of 4.5 million units. Therefore percentage increase will be 4.5/25.5 x 100 = 18%.

Similarly for TV 2007 it will be, 2.5/22.5 x 100 = 11.11 %. For Laptop 2006 it will be, 7.5/15 x 100 = 50 % and for TV 2009, it will be 5/25 x 100 = 20 %. So for laptop 2006, the percentage increase in sales is the highest. Thus, the correct answer is C.