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Question
A random survey of the number of children of various age groups playing in a park was found as follows:
| Age (in years) | Number of children |
| 1 - 2 | 5 |
| 2 - 3 | 3 |
| 3 - 5 | 6 |
| 5 - 7 | 12 |
| 7 - 10 | 9 |
| 10 - 15 | 10 |
| 15 - 17 | 4 |
Draw a histogram to represent the data above.
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Solution
Here, it can be observed that the data has class intervals of varying width. The proportion of children per 1 year interval can be calculated as follows.
| Age (in years) | Frequency (Number of children) | Width of the class | Length of the rectangle |
| 1 - 2 | 5 | 1 | `(5 xx 1)/1` = 5 |
| 2 - 3 | 3 | 1 | `(3 xx 1)/1` = 3 |
| 3 - 5 | 6 | 2 | `(6 xx 1)/2` = 3 |
| 5 - 7 | 12 | 2 | `(12 xx 1)/2` = 6 |
| 7 - 10 | 9 | 3 | `(9 xx 1)/3` = 6 |
| 10 - 15 | 10 | 5 | `(10 xx 1)/5` = 2 |
| 15 - 17 | 4 | 2 | `(4 xx 1)/2` = 2 |
Taking the age of children on the x-axis and the proportion of children per 1 year interval on the y-axis, the histogram can be drawn as follows:
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