Question 61095: which one of these numbers are prime and how do i show my work?
12,31,99,1
i think 1 is prime because you only have 0,1
Found 2 solutions by venugopalramana, praseenakos:
Answer by venugopalramana(3286)   (Show Source):
You can put this solution on YOUR website! which one of these numbers are prime and how do i show my work?
12,31,99,1
i think 1 is prime because you only have 0,1
PRIME NUMBER IS
A NUMBER WHICH HAS NO FACTORS (THAT IS NOT DIVISIBLE LEAVING ZERO REMAINDER
-BY ANY NUMBER)EXCEPT 1 AND ITSELF.
BUT THERE IS ANEXCEPTION..AS A RULE 1 IS NOT CLASSIFIED AS A PRIME NUMBER.
THE ONLY METHOD IS TO CHECK BY DIVISION STARTING FROM 2,3,ETC...
12 IS NOT AS IT IS DIVISIBLE BY 2
31 IS PRIME AS 2,3,5,7 ARE NOT FACTORS..NEED NOT GO BEYOND SINCE 7*5=35>31
THAT IS SECOND FACTOR IS LESS THAN THE FIRST FACTOR AND TILL THIS STAGE SECOND FACTOR IS MORE THAN THE FIRST FACTOR 5*7=35>31
99 IS NOT PRIME...AS IT IS DIVISIBLE BY 3
1 IS NOT PRIME BY DEINITION
Answer by praseenakos(2)  (Show Source):
You can put this solution on YOUR website! which one of these numbers are prime and how do i show my work?
12,31,99,1
i think 1 is prime because you only have 0,1
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solution:
A prime number is a positive integer that has exactly two positive integer factors, 1 and itself.
for example,
Facors of 2 = 1, 2
Factors of 3 = 1, 3
Factors of 4 = 1, 2, 4
Factors of 5 = 1, 5
Factors of 6 = 1, 2, 3, 6
Factors of 7 = 1, 7
Factors of 8 = 1, 2, 4, 8
Factors of 9 = 1, 3, 9
Factors of 10 = 1, 2, 5, 10
Here 2, 3, 5, 7 have factors 1 and the number itself only
so these anumbers are prime.
If we list the factors of 28, we have 1, 2, 4, 7, 14, and 28. That's six factors. If we list the factors of 29, we only have 1 and 29. That's two factors. So we say that 29 is a prime number, but 28 isn't.
Note that the definition of a prime number doesn't allow 1 to be a prime number: 1 has only one factor, namely 1. Prime numbers have exactly two factors, not "at most two" or anything like that. When a number has more than two factors it is called a composite number.
Here are the first few prime numbers:
2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97, 101, 103, 107, 109, 113, 127, 131, 137, 139, 149, 151, 157, 163, 167, 173, 179, 181, 191, 193, 197, 199, etc.
NOW LET'S COME BACK TO YOUR QUESTION.
12,31,99,1
Factors of 12 =1, 2, 3, 4, 6, 12
That means 12 has more than two factors. So it is not a prime.
factors of 31 = 1, 31
That means 31 has only two factors : 1 and 31(the number itself)
so 31 is a prime.
Factors of 99 = 1, 3, 33, 91
Tat means 99 has more than two factors .
So 99 is not a prime.
1 has only one factor, namely 1. Prime numbers have exactly two factors,
So 1 is not a prime.
Additional Information:
1 is neither a prime nor a composit.
2 is only EVEN prime number.
BYE!!!!!!!!!!!!!!!!
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