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Question
Draw a histogram for the following distribution and estimate the mode:
| Marks% | 30-39 | 40-49 | 50-59 | 60-69 | 70-79 | 80-89 | 90-99 |
| No. of students | 14 | 26 | 40 | 92 | 114 | 78 | 36 |
Solution
| Marks % | No. of students |
| 29.5-39.5 | 14 |
| 39.5-49.5 | 26 |
| 49.5-59.5 | 40 |
| 59.5-69.5 | 92 |
| 69.5-79.5 | 114 |
| 79.5-89.5 | 78 |
| 89.5-99.5 | 36 |
(a) Take 1cm = 1 unit and plot marks % on x-axis and no. of students on y-axis.
(b) Draw a bar graph for the given data.
(c) From the histogram it is clear that class 69.5-79.5 has highest frequency i.e. 114
(d) Join the ends of the corresponding frequencies which meet at P and drop a perpendicular on the x-axis from P to Q. Q is the mode. Therefore, Mode = 73
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