THE CRESCENT PUZZLE.
(
Patchwork Puzzles)
Here is an easy geometrical puzzle. The crescent is formed by two
circles, and C is the centre of the larger circle. The width of the
crescent between B and D is 9 inches, and between E and F 5 inches. What
are the diameters of the two circles?
Answer:
Referring to the original diagram, let AC be x, let CD be x - 9, and let
EC be x - 5. Then x - 5 is a mean proportional between x - 9 and x, from
which we find that x equals 25. Therefore the diameters are 50 in. and
41 in. respectively.