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Math problem: In the following two pictures, the square has an area of 40 square centimeters. Which part of the shadow area is larger? How much bigger?
1,

Diameter of circle = side length of square,

Radius of circle = length of square side ÷2

Shadow area 1= square area-circular area.

=40- (square side length ÷2)x (square side length ÷2)x3. 14

=40- (square side length x square side length) ÷2÷2x3. 14

=40-40÷2÷2x3. 14

=8.6 (square centimeter)

2,

Diameter of circle = diagonal length of square,

Radius of circle = diagonal length of square ÷2

Shadow area 2= circular area-square area

= (square diagonal length ÷2)x (square diagonal length ÷2)x3. 14-40

= (square diagonal length x square diagonal length) ÷2÷2x3. 14-40

= (square side length x square side length x square side length) ÷2÷2x3. 14-40, Pythagorean theorem

=(40+40)÷2÷2x3. 14-40

=22.8 (square centimeter)

Shadow area 2 is greater than 1: 22.8-8.6= 14.2 (square centimeter).