The radius of the smallest circle containing the symmetric figure composed of the three squares shown at the right is:
- none of these
We’ll design a circle that passes through A, B, C, and D. Its center will be at O, on the line bisecting the symmetric figure, and its radius will be x.
We see that x is the hypotenuse of two right triangles, OEB and OFC. Let OF = t. Then
We see that x is approximately 1.29, which is not too different from answer choice (c), but (d) is the exact answer.