The 1:3 ratio means that the distance from A to the point is 1/4 of the distance from A to B.
The difference of y-coordinates is 10-8 = 2. 1/4 of that is 2·1/4 = 1/2, so the point of interest will have y-coordinate 8 + 1/2 = 8 1/2. This apparently corresponds to the first selection:
... (6 1/2, 8 1/2)
Your answer is D. Hope this helps!
4 5/8 as an improper fraction is 37/8
——> 8*4=32 32+5=37
As a mixed number it is the same I think. 5 can’t decide into 8 so it stays 4 5/8.
Hopefully this helps...