Assuming all the numbers are the same (chances are that they are seeing as they use the same variable ((the Greek lowercase letter known as Psi - Ψ)), then we should determine the area based on formulas.
For the leftmost shape, you have to use the length * width formula TWICE and then subtract the missing area value to find the remaining area (which is--even after subtracting, the greatest than out of all the other shapes).
For the middle shape, the formula you use is length * width-- which is less than that of the leftmost shape, but more than the rightmost shape.
For the rightmost shape, the formula you use is (length * width)/2--which is half of the middle shape and less than the largest shape.
