If you trying to answer what would be on all the sides if it were to be equal then 51 would be the answer if it's not what the question seems I will try and answer, but be more explanatory.
Given:
The frequency distribution table.
To find:
The mean average score on a test.
Solution:
The frequency distribution table is

x a xa
y b yb
z c zc
Sum a+b+c xa+yb+zc
Now, the mean average score on the test is


Therefore, the mean average score on the test is
.
Answer: (1.5, 3.5)
Explanation:
Find the slope by using the coordinates for points L and K.
3 - 4 = -1
5 - (-2) = 7
Slope = -1/7
Then you plot your points on the graph.
But you want to half your slope to find the midpoint. So your slope would now be -0.5/3.5.
And when you follow that slope, you will plot down the coordinate (1.5, 3.5), which is the midpoint.
Hope this helped! :3
(Also don’t mind the 19 at the top left)