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Question
Explain the reading and interpretation of bar graphs.
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Solution 1
First step in reading a bar graph is to know what it represents or what is the information given by it, for this we read the captions. Which are generally written just below the horizontal line ( x- axis) and adjacent to vertical line (y - axis )
After knowing that what a bar graph represents, we read the scale so that we can know the precise value in the given data.
After reading a bar graph one must be able to draw certain condusions from it. Drawing some conditions from a given bar graph means interpretation of the bar grph.
Solution 2
A bar graph is a diagram consisting of a sequence of vertical or horizontal bars or rectangles, each of which represents an equal interval of the values of a variable, and has height proportional to the quantities of the phenomenon under consideration in that interval. A bar graph may also be used to illustrate discrete data, in which case each bar represents a distinct circumstance.
While drawing a bar graph, we keep in mind that
1. The width of the bars should be uniform throughout.
2. The gap between any two bars should be uniform throughout.
3. Bars may be either horizontal or vertical.
Each bar must be of same width and the gap between them must be uniform. Make sure that the width of the bars and the gap between them should not be necessarily same.
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