+23246 I'm assuming that the distance between each two circles is 1 m.
The inner-most circle has a radius of 1m, so its area is pi·12 = 1·pi m2.
The next circle has a radius of 2 m so its area is 4·pi m2 and the area of the ring is 3·pi m2.
The next circle has a radius of 3 m so its area is 9·pi m2 and the area of the ring is 5·pi m2.
The outer-most circle has a radius of 4 m so its area is 16·pi m2 and the area of the ring is 7·pi m2.
The area of the white portion is 6·pi m2 and the area of the grey portion is 10·pi m2.
