We need to find the expression that represents the average of three test scores
At first : the average = the sum of the data over the number of the data
We have 3 test scores : x , y and z
The sum of the scores = x + y + z
The number of the scores = 3
so, the average will be :
[tex]\frac{x+y+z}{3}[/tex]So, the answer is : ( x + y+ z )/3
