Answer: A) 82.3
Step-by-step explanation:
Mean= average
To find mean, you add up all the numbers and divide by the number of numbers.
In this case you do:
(81+78+83+89+80+87+78) ÷ 7
81+78+83+89+80+87+78
=576
Now, divided by 7
576 ÷ 7
= 82.2857142857
Round to nearest tenths place
= 82.3