=340 1÷38,

=89.5 (points);

(2) the first group: 8 10÷9=90 (points),

Group 3: 922÷ 10=92.2 (point),

The fourth group: 774÷9=86 (points),

Because: 92.2 > 90 > 89.5 > 86;

So the average score of the third group is high;

A: The average score of the whole class is 89.5, and the average score of the third group is higher.