The blood groups of 30 students of Class VIII are recorded as follows: A, B, O, O, AB, O, A, O, B, A, O, B, A, O, O, A, AB, O, A, A, O, O, AB, B, A, O, B, A, B, O. By representing this data in a frequency distribution table, find out the most common and the rarest blood group among these students.

The blood groups of 30 students of Class VIII are recorded as follows:

1.	The blood groups of 30 students of Class VIII are recorded as follows: A, B, O, O, AB, O, A, O, B, A, O, B, A, O, O, A, AB, O, A, A, O, O, AB, B, A, O, B, A, B, O. By representing this data in a frequency distribution table, find out the most common and the rarest blood group among these students.
Answer» The blood groups of 30 students of Class VIII are recorded as follows: A, B, O, O, AB, O, A, O, B, A, O, B, A, O, O, A, AB, O, A, A, O, O, AB, B, A, O, B, A, B, O. By representing this data in a frequency distribution table, find out the most common and the rarest blood group among these students.