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Are all odd numbers prime numbers?
No because 2 is an even number which is also a Prime number that has only two factors which are itself and one.
What is a counter example for the statement that all odd numbers are prime?
9 = 3 x 3 15 = 3 x 5 etc. Any odd number that is composite. But 2 is a prime number which is not an odd number. [Wrong question: that is a counter example to all primes are odd numbers]
What odd number between 11 and 21 is the product of two prime numbers?
13 is prime so it is not the number. 15 is the product of 3 and 5, two prime numbers, so it fits the conditions. 17 is prime so it is not the number. 19 is prime so it is not the number. 15 is the only odd number between 11 and 21 that fits the conditions. However, if 21 is included in the range, it also is the product of two prime numbers: 3 x 7.
What odd number less than 20 has 2 different prime factors?
The smallest prime numbers, after 2, are 3 and 5. 3 x 5 = 15.
What is the sum of the first 15 prime numbers?
the sum of the first 15 prime numbers is 328 .
When all the prime factors are odd the number is odd?
odd and prime are two different things ,but odd numbers can be prime or composite just depends if you can multiply it with another number except 1 here's an example 7 ( 7 is odd and is prime because it has 2 factors "7 & 1" 15 is odd ,but not prime because 5x3 is 15 and 15x1 is 15 5 and 3 are factors of 15 so all odd numbers are not prime all even numbers are composite except the number 2.
Is odd numbers prime numbers?
prime number is a number that could only be divided by itself and one. odd numbers are naturally not divisible by 2 but odd numbers can be divisible by other numbers. one example is 15. 15 is divisible by itself and one but also by 3 and 5.
Are all odd numbers prime why or why not?
NO. Not all odd numbers are prime like 9, 15, 21, 27,... because they have other factors aside from 1 and itself.
Are all odd numbers prime numbers?
No because 2 is an even number which is also a Prime number that has only two factors which are itself and one.
What is the odd number between 10 and 20that are not prime number?
The numbers between 10 and 20 that are not prime are 12, 14, 15, 16 and 18. So 15 is the odd number and the rest are even numbers.
Is the product of 2 prime numbers always even?
No, the product of 2 prime numbers is not always even. If one of the prime numbers is 2, then the product will be even. However, if both prime numbers are odd, then the product will be odd.
What is the smallest odd number that is the sum of three different prime numbers?
15
Do prime numbers have to be odd and composite numbers have to be even?
No. All prime numbers except for the number 2 are odd. However, most odd numbers are composite numbers. All even numbers greater than 2 are composite numbers. So, prime numbers do not need to be odd, since one prime number is even. Also, composite numbers do not need to be even.Here are some composite odd numbers:9 = 3 x 333 = 3 x 1175 = 5 x 15
How many prime numbers are there under 50?
There are 15 prime numbers less than 50.
What is the probabiliy of selecting odd or prime numbers from 1 to 50?
The probabiliy of selecting odd or prime numbers from 1 to 50. First find out the probability of selecting odd numbers : 25/50 is 1/2. Lets find out the probability of selecting prime numbers: 15 / 50 . so, total is 40/ 50 is 0.82.
Is every odd number is prime or not?
No, there are many odd numbers that are not prime: 9, 15, 21, 25, 27, etc. However, 2 is the only even number that is prime, since all other even numbers are divisible by 2.
How many odd numbers under 19?
1, 3, 5, 7, 9, 11, 13, 15, 17There are a total of 9 odd numbers under 19.
