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The area of the ring is 200 cm square, the radius of the outer circle is 10 cm, and the radius of the inner circle is 10 cm
Let the radius of the small circle be X
π10*10-πx*x=200
The shape of the ring is as shown in the figure. Its area is 200cm & # 178;. The radius of the big circle on the outside is 10cm. What is the radius of the small circle on the inside
Let the radius of the inner circle be x cm
Then the area is π * 10 & # 178; - π X & # 178; = 200
πx²=100π-200
x²=(100π-200)/π
So x = 10 √ (π & # 178; - 2 π) / π
So the radius of the inner circle is 10 √ (π & # 178; - 2 π) / π cm
There is a circular ring with an area of 200cm and 178;, the radius of the outer circle is 10cm, and the radius of the inner circle is 10cm? (equation)
The correct answer is 60
Let the radius of the small circle be xcm
10^2*3.14-x^2*3.14=200
x^2*3.14=114
x=6cm
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