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Question
The blood groups of 30 students are recorded as follows:
A, B, O, A, AB, O, A, O, B, A, O, B, A, AB, B, A, AB, B, A, A, O, A, AB, B, A, O, B, A, B, A
Prepare a frequency distribution table for the data.
Solution
The number of students who have a certain type of blood group is called the frequency of those blood groups.
A frequency distribution table for the given data is given below:
| Blood group | Tally marks | Number of students (Frequency) |
| A | `\cancel(bb|bb|bb|bb|)` `\cancel(bb|bb|bb|bb|) bb|bb|` | 12 |
| B | `\cancel(bb|bb|bb|bb|) bb|bb|bb|` | 8 |
| AB | `bb|bb|bb|bb|` | 4 |
| O | `\cancel(bb|bb|bb|bb|) bb|` | 6 |
| Total | 30 |
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