Sorry, I dont know how to contact you
Ana
2006-08-12 16:16:11 · 4 answers · asked by Ilusion 4 in Science & Mathematics ➔ Mathematics
THIS IS NOT A QUESTION, ITS A MESSAGE TO SOMEONE. I AM A TEACHER OF MATHEMATICS, I KNOW THAT 51 IS NOT A PRIME. THANK YOU
ANA
2006-08-12 16:28:25 · update #1
all u have to do is usually click there name but i am guessing u might know that lol
2006-08-12 18:39:01 · answer #1 · answered by hillbilly271 3 · 1⤊ 1⤋
3*17=51.
In fact it's easy to tell if a two digit number is not prime.
- If it ends in 0,2,4,6,8 then it's divisible by 2.
- If it ends in 0,5 then it's divisible by 5.
- If you sum its digits and that is divisible by 3, then your number is divisible by 3. In this case 5+1=6 is divisible by 3.
- Only three left to remember 49 = 7*7, 77 = 7*11 and 91= 7*13.
The rest are primes. Some people say that 91 is the number most often misquoted as a prime.
2006-08-12 16:23:59 · answer #2 · answered by Anonymous · 0⤊ 1⤋
51 is not a prime number, because 51 is divisible by 3 and 17....
2006-08-12 17:10:50 · answer #3 · answered by Anonymous · 0⤊ 1⤋
is not 3x17=51, not prime...not even grade A
2006-08-12 16:18:46 · answer #4 · answered by Anonymous · 0⤊ 1⤋