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Question
A Mathematics aptitude test of 50 students was recorded as follows:
| Marks | 50 - 60 | 60 - 70 | 70 - 80 | 80 - 90 | 90 – 100 |
| No. of Students | 4 | 8 | 14 | 19 | 5 |
Draw a histogram from the above data using a graph paper and locate the mode.
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Solution
The histogram for the given data can be drawn by taking the marks on the x-axis and the number of students on the y-axis.
To locate the mode from the histogram, we proceed as follows:
1) Find the modal class. Rectangle ABCD is the largest rectangle. It represents the modal class, that is, the mode lies in this rectangle. The modal class is 80 – 90.
2) Draw two lines diagonally from the vertices C and D to the upper corners of the two adjacent rectangles. Let these rectangles intersect at point H.
3) The x-value of the point H is the mode. Thus, mode of the given data is approximately 83.
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