Their are two intersecting circles. Circle 2's center sits on a point on the circumference of Circle 1.

Circle 2 has to overlap HALF of Circle 1's area.

Given that we know the diameter(/radius and circumference etc...) of Circle 1.

How do I work out the radius of Circle 2 (such that Circle 2 overlaps half the area of Circle 1)

Please any help would be apreciated.

Thanks in advance