Stuck on question

Question

The chart below shows the number of that A students received on each of their last year. What is the mean number of A's received?

test number number of A’s

1. 6

2. 9

3. 4

4. 9

5. 9

6 8

Answer 1

45/6 = 15/2 = 7.5

= mean = arithmetic average = sum divided by number of grades = (6+4+9+9+9+8)/6 =45/6