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Question
The heights of 50 students, measured to the nearest centimeters, have been found to be as follows:-
| 161 | 150 | 154 | 165 | 168 | 161 | 154 | 162 | 150 | 151 |
| 162 | 164 | 171 | 165 | 158 | 154 | 156 | 172 | 160 | 170 |
| 153 | 159 | 161 | 170 | 162 | 165 | 166 | 168 | 165 | 164 |
| 154 | 152 | 153 | 156 | 158 | 162 | 160 | 161 | 173 | 166 |
| 161 | 159 | 162 | 167 | 168 | 159 | 158 | 153 | 154 | 159 |
(i) Represent the data given above by a grouped frequency distribution table, taking the class intervals as 160 - 165, 165 - 170, etc.
(ii) What can you conclude bout their heights from the table?
Solution
(i) A grouped frequency distribution table has to be constructed taking class intervals 160 − 165, 165 − 170, etc. By observing the data given above, the required table can be constructed as follows.
| Height (in cm) | Number of students (frequency) |
| 150 − 155 | 12 |
| 155 − 160 | 9 |
| 160− 165 | 14 |
| 165 − 170 | 10 |
| 170 − 175 | 5 |
| Total | 50 |
(ii) It can be concluded that more than 50% of the students are shorter than 165 cm.
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