Is 11 prime or composite?
http://www.mathsisfun.com/prime-composite-number.html
To determine whether 11 is prime or composite, we need to understand the definitions of prime and composite numbers.
A prime number is a positive integer greater than 1 that has no positive divisors other than 1 and itself. In other words, a prime number is only divisible by 1 and itself.
On the other hand, a composite number is a positive integer greater than 1 that can be divided evenly by at least one other positive integer other than 1 and itself.
To determine if 11 is prime or composite, we can start by dividing it by smaller prime numbers. The first few prime numbers to consider are 2, 3, 5, and 7. If any of these numbers divide 11 evenly, then 11 is composite. However, if none of these numbers divide 11 evenly, then 11 is prime.
Let's check if 11 is divisible by any of these prime numbers:
- 11 ÷ 2 = 5.5 (not a whole number)
- 11 ÷ 3 = 3.67 (not a whole number)
- 11 ÷ 5 = 2.2 (not a whole number)
- 11 ÷ 7 = 1.57 (not a whole number)
Since none of these divisions result in a whole number, we can conclude that 11 is not divisible by any prime numbers less than itself. Therefore, 11 is a prime number.
In summary, 11 is a prime number because it is only divisible by 1 and itself, and no smaller prime numbers divide it evenly.