## Wednesday, June 10, 2015

### Special properties of number 10 (Today’s Date)

1. 10 is the base of our number system.
2.10 is the sum of the first 3 prime numbers: 10 = 2 + 3 + 5
3. 10 is both a triangular (1 + 2 + 3 + 4 = 10) and tetrahedral number.
4.10 is asemiprime number. A semiprime is a natural number that is the product of two (not necessarily distinct) prime numbers. The semiprimes less than 100 are 4, 6, 9, 10, 14, 15, 21, 22, 25, 26, 33, 34, 35, 38, 39, 46, 49, 51, 55, 57, 58, 62, 65, 69, 74, 77, 82, 85, 86, 87, 91, 93, 94, and 95.
The Chemical Element Neon has an atomic number of 10.
5. 10! = 6! x 7! = 3! x 5! x 7! (Unique solution to the factorial equation n! =a! x b! x c! with consecutive prime factors)
6. In most advertisements, including newspapers, the time displayed on a watch is approximately 10:10. The reason for this is to "frame" the logo of the watch maker. The hands at that number cause the eyes to look right at the logo!
7. Marion's theorem states that the area of the central hexagonal region determined by trisection of each side of any triangle ABC and connecting the corresponding points with the opposite vertex is exactly one tenth (1/10) the area of the whole triangle ABC.