Table of contents  
What are Bar Charts?  
The Use of Bar Charts to Show Deviations  
Representation of Percentage on a Stacked Bar Chart  
Solved Examples 
Bar charts are one of the easiest, graphically attractive and hence most commonly used methods of presenting all types of data. They are especially useful for representing various data series.
Bar Chart
Now let's have a look at the different kinds of bar charts and the kinds of data that can be represented on a bar chart.
The simple bar chart has one continuous variable charted along with one discrete variable.
Figure below shows an example of a Simple Bar Chart.
Simple Bar Chart
One of the primary limitations of the simple bar chart is that it can only be used to display a single continuous variable.
What is the ratio of the total sales of branch B2 for both years to the total sales of branch B4 for both years?
Deviation bars are useful for graphic presentation of continuous variables which can have both positive and negative values, i.e., surplus or deficit, net profit or loss, net of imports and exports.
In general continuous variables which have both positive and negative values are best represented on bar charts.
Sometimes stacked bars can also be used to represent the breakup of some continuous variable. The figure below will make it clear.
What was the percentage of students who cleared CAT in 2000?
(i) In how many of the given years was the exports at least 10% more than the imports?
(A) 0 (B) 1 (C) 2 (D) 3 (E) 4
Solution:
(a) In 1994, exports = 80
Imports = 70
10% of imports = (70 x (10/100) = 7)
⇒, Exports > imports + 10% of imports
(b) In 1995, exports = 130
Imports = 120
10% of Imports =(120 x (10/100) = 12)
⇒ Exports < imports + 10% of imports
(c) In 1996, exports = 140
Imports = 150
⇒ Exports < Imports so we need not consider this case.
(d) In 1997, Exports = 112
Imports = 100
10% of Imports = (100 x (10/100) = 10)
⇒ Exports > Imports + 10% of imports(e). In 1998, Exports = 170
Imports = 160
10% of Imports = (160 x (10/100) = 16)
⇒ Exports < Imports + 10% of Imports
(f) Exports = 160
Imports = 150
10% of Imports = (150 x (10/100) = 15)
⇒ Exports < Imports + 10% if Imports
⇒The given condition was satisfied in two years.
Choice (C) is the correct answer.
(ii) What were the average exports for the given period (in Rs. 000' crores)?
(A) 145 (B) 132 (C) 126 (D) 119 (E) 138
Thus choice (B) is the right answer.
(iii) From 1995 to 1999, in which year was the percentage growth In exports, when compared to the previous year, the highest?
(A) 1995 (B) 1996 (C) 1997 (D) 1998 (E) 1999
Solution: Export in a year exceeded that in the previous year in 1995, I996 and I998. Percentages by which exports in I995, I996 and 1998 exceed the exports in the previous year were:
Only in I995 was the growth more than 60%
Thus choice (A) is the correct answer.
(iv) What is the simple average annual growth rate in the imports from I994 to 1999?
(A) 15 (B) 18 (C) 19 (D) 21 (E) 23
Solution:
Imports in 1994 (in '000 crores) = 70
Imports in 1999 (in '000 crores) = 150
Thus choice (E) is the correct answer.
(v) Among the years in which the imports, as well as exports, exceed those in the previous years, In how many years was the percentage increase in imports less than the percentage increase in exports?
(A) 0 (B) 1 (C) 2 (D) 3 (E) 4
Solution: The imports, as well as exports, exceeded those in the previous years in I995, I996 and 1998. In none of the years was the given condition satisfied.
Thus choice (A) is the correct answer.
Q.2. Production of paper (in lakh tonnes) by three companies X, Y and Z over the years. Study the graph and answer the questions that follow.
(i) What is the difference between the production of company Z in 1998 and company Y in 1996?
Ans: Required difference
= [(45  25) * 1,00,000] tones
= 20,00,000 tons.
(ii) What is the ratio of the average production of company X in the period 19982000 to the average production of company Y in the same period?
Ans: Average production of company X in the period 19982000 = [1/3 * (25 + 50 + 40)] = (115/3) lakh tons. Average production of company Y in the period 19982000 = [1/3 * (35 + 40 + 50)] = (125/3) lakh tons. Required ratio = (115/3)/(125/3) = 115/125 = 23/25
(iii) What is the percentage increase in the production of company Y from 1996 to 1999?
Ans: Percentage increase in the production of company Y from 1996 to 1999 = [(40  25)/25 * 100]% = (15/25 * 100)% = 60%
(iv) The average production for five years was maximum for which company?
Ans: For company
(v) In which year was the percentage of production of company Z to the production of company Y the maximum?
Ans: The percentage of production of company Z to the production of company Z for various years are:
Clearly, this percentage is highest for 1996.
197 videos151 docs200 tests

1. What are bar charts? 
2. How can bar charts be used to show deviations? 
3. How can percentages be represented on a stacked bar chart? 
4. Can you provide an example of how to interpret a bar graph? 
5. Are there any solved examples available for better understanding bar graphs and their interpretation? 
197 videos151 docs200 tests


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