I think we can use similar triangles to solve this
Area of smaller circle = pi * radius^2
1 = pi * radius^2
1 / pi = radius^2
√[1/pi] = radius of smaller circle
Call the radius of the larger circle, R
And we have this
3√(1/pi) 3√(1/pi) + R
_____ = _____________ simplify
√(1/pi) R
3R = 3√(1/pi) + R
2R = 3√(1/pi)
R = (3/2)√(1/pi)
So the area of the larger circle =
pi [( 3/2) √(1/pi) ] ^2 =
9/4 units^2 =
2.25 units^2