In this section, the following topics are discussed with example

BAR CHARTS

bar chart or bar graph is a chart or graph that presents grouped data with rectangular bars with lengths proportional to the values that they represent. The bars can be plotted vertically or horizontally. A vertical bar chart is sometimes called a Line graph.

The significant problems we have cannot be solved at the same level of thinking with which we created them.

ALBERT EINSTEIN

EXAMPLES

Ex 1:

Understand the chart and answer the following questions:

FOREIGN EXCHANGE RESERVES OF A COUNTRY ( IN MILLION US \$)

1.The ratio of the number of years, in which the foreign exchange reserves are above the average reserves, to those in which the reserves are below the average reserves is?

Sol:

Average foreign exchange reserves over the given period = 3480 million US \$.

The country had reserves above 3480 million US \$ during the years 2002-2003, 2006-2007 and 2007-2008, i.e., for 3 years and below 3480 million US \$ during the years 2001-2002, 2003-2004, 2004-05, 2005-06 and 2008-09 i.e., for 5 years.

Hence, required ratio = 3 : 5.

2. For which year, the percent increase of foreign exchange reserves over the previous year, is the highest?

Sol:

There is an increase in foreign exchange reserves during the years 1992 – 1993, 1994 – 1995, 1996 – 1997, 1997 – 1998 as compared to previous year (as shown by bar-graph).

The percentage increase in reserves during these years compared to previous year are:

For 1992 – 1993 =[(3720-2640)/2640]x100 = 40.91%

For 1994 – 1995 =[(3360-2520)/2520]x100 = 33.33%

For 1996 – 1997 =[(4320-3120)/3120]x100 = 38.46%

For 1997 – 1998 =[(5040-4320)/4320]x100 = 16.67%

Clearly, the percentage increase over previous year is highest for 1992 – 1993.

Thus in this section we learned about the concepts of Bar Charts Data Interpretation question format. In next section, we will learn about the second type of Data Interpretation question format – The Line Graphs.