Ancient Chinese Coin

$A_{square}=A_{circle}-A_{coin}$

$A_{square}=3^{2}π -7π$

$A_{square}=9π -7π$

$A_{square}=2π$

$A_{square}= \boxed{6.284}$

Total Area of Circle = pi(3^2) = 9*pi

Left off area = 7*pi

=> Area of Square = 9 pi - 7 pi = 2* pi = 6.284

Area of circle in coin is pie R square =pie X 3 X3 = 9pie area of square given is 7 pie so remaing are is 9 pie -7 pie =2 X 3.142 = 6.284 Ans K.K.GARg.India

2pie(r)square=9pie Bcoz r =3, face area=7pie, so 9pie-7pie=2pie,2*3.142=6.284

Area of the Square = Pi R^2 - 7 Pi =9 Pi - 7 Pi =2*Pi =6.284

(3.14)(9^2) - x = 7(3.14) x = 2(3.142) x = 6.284

A= ACIRCLE - A COIN=9Π -7Π=2Π=6.284

Acircle=7*3.1=21.7 aprox then by guessing the ratio, the square will be 6.284 !!!!!

Technically this problem should have no solution as the area is considered to be 7pi and not 7pi cm. Thus it could be 7pi mm or any other unit...but I assume this was just a type. In which case

A(square)=A(Circle)-A(Coin)

A(square)=3^2pi-7pi

A(square)=2pi

or 6.284

Total area of the circle is Pi r^2 = 9 pi. With the exclusion of the square, area is reduced to 7pi. Therefore the area of the cut-out square is 2 pi = 2*3.142= 6.284

Hey yo,

Given the radius of a circle = 3cm, the area of a coin's side = 7 pie,

Area of a circle = Area of a square + Area of a coin's side,

Area of a square = Area of a circle - Area of a coin's side,

Area of a square = (3.142)(3)(3) - 7(3.142) = 6.284 cm^2...

Thanks ah...