Given:
Diameter of outer circle = 20 inches.
We need to find the Area of the outer circle to get the radius of the inner circle.
Area = πr²
Outer circle Area = 3.14 (10in)² = 314 in²
314 in² 64% probability = 200.96 in² Area of the inner circle.
200.96 in² = 3.14 * r²
200.96 in² / 3.14 = r²
64 in² = r²
√64 in² = √r²
8 in = r
radius of inner circle is 8 inches.
