Question 759407
I am assuming that the circle's diameter is 
equal to the side length of the square, namely 40cm.
Area of Square = length * width = 40*40 = 1600cm^2
Area of Circle = Pi*r^2 = Pi * 20^2 = 1256.6 cm^2
 1600 - 1256.6 cm^2 = 343.4ins^2 left over.
Hope this helps.
:-)