With an average of 4/3, to obtain the number of cups needed to obtain a height of 50m, we have:
50 / (4/3)
= 50 * 3/4
= 150/4
= 37.5
From the answer, we can see that the number of cups is not really proportional to the height of the stack, because the average of stack one and stack 2 are different.
