1/4 = 0.25.....................2 and 5 are half of all single digit primes.........3 and 7 are the hidden ones...........................they come out with addition and subtraction............as I put before.........5 + 2 = 7.............5 - 2 = 3............................all 4 single digit primes...............2/5 = 0.40....................using 2 and 5 as simple sieves..........they cut out 60% of all numbers above them from ever being prime...............................2 cuts out 1/2 of the number line................5 cuts out every 5th number...........every middle number in a 0 to 0 10 number digit sequence..........they overlap at the zeros..................................they thus leave 40% of the number line.........above them.......from being prime.............2/5 = 0.40.........................surprising connections between numbers........number theory.

3 is a more powerful sieve then 5.................it cuts out every 3rd number........but to me......it is easier to see 5 conceptually................5 10 5 10 5 10..................every zero and middle number.......like 50................like 5050.........the sum of 0 - 100.......or 1 - 100..................