The given histogram represents the number of plants of different heights grown on a school campus. Study the graph carefully and answer the following questions:
(a) Make a frequency table with respect to the class boundaries and their corresponding frequencies.
(b) State the modal class.
(c) Identify and write the mode of the distribution.
(d) Find the number of plants whose height is between 80 cm and 90 cm.
(a) Reading the heights of the bars gives the following frequency table:
| Height (cm) | Number of plants |
|---|---|
| 30–40 | 4 |
| 40–50 | 2 |
| 50–60 | 8 |
| 60–70 | 12 |
| 70–80 | 6 |
| 80–90 | 3 |
| 90–100 | 4 |
(b) The greatest frequency is 12, corresponding to the class 60–70 cm.
Therefore, the modal class is 60–70 cm.
(c) From the graph, the mode of the distribution is 64 cm.
(d) The frequency corresponding to 80–90 cm is 3.
Therefore, 3 plants have heights between 80 cm and 90 cm.
More ICSE Moderate level questions
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