The correct answer is Choice C.
The ratio given is 2 to 3. All of the choices give the total of 15 glass as needed. However, only choice C is also in the ratio of 2 to 3.
6/9 can be reduced to the fraction 2/3 by dividing by 3.
X - 10
in function...
v = f(X - 10)
The area of a parallelogram is given by

Now, if we consider the 9.9 inches side as the base, then the height is the one labeled with 5.5 inches.
If instead we choose the 11 inches side as the base, the height is h.
So, we can express the area in this two equivalent ways:

Solving for h, we have

The answer is 21, because if you multiply 21 times 3 you get 63