UPSC CDS 2 2022 Math Paper

Area of square =(‌ side ‌)2
Area of circle =‌

π

4

d2Using the above concept
Area of square
A1=(‌ side ‌)2
A1=(16)2=256cm2
Now, the area of the circular disc
A2=‌

π

4

(14)2=‌

22

4×7

×142cm2
⇒A2=154cm2
The area of the remaining part of the plate =A1−A2
⇒A=(256−154)cm2=102cm2
The weight of 256cm2 plate =128‌gm
The weight of 102cm2 of the plate =‌

128×102

256

=51‌gm