How to find Prime Numbers from 1 to 100.
How to find Prime Numbers from 1 to 100 Easy Method...... Sieve of Eratosthenes. Round 1 : Cross out 1 because it is not a prime number. Round 2 : Encircle 2, cross out all the multiples of 2, other than 2 itself, i.e. 4, 6, 8 and so on. Round 3 : You will find that the next uncrossed number is 3. Encircle 3 and cross out all the multiples of 3, other than 3 itself. Round 4 : The next uncrossed number is 5. Encircle 5 and cross out all the multiples of 5 other than 5 itself. Round 5 : Continue this process till all the numbers in the list are either encircled or crossed out. All the encircled numbers are prime numbers. All the crossed out numbers, other than 1 are composite numbers. This method is called the Sieve of Eratosthenes.