How do you find prime numbers from 1-100?

Answer 1

1. write all the numbers from 1 to 100

2. cross off 1 as it is itself and it is not needed

3. except for 2 cross out all the multiples of 2 (the even numbers)

4. except for 3 cross out all the numbers that are a multiple of three(some would already cross off after you get rid of the even numbers except for 2)

5. except for 5-because 4 is crossed off- cross off all the multiples of 5

6. except for 7-because 6 is crossed off- cross off all the multiples of 7

7. repeat this until you get to 100-which would already be crossed off- and all the numbers that are not crossed off are the prime numbers

prime numbers = numbers that divide by 1 and itself e.g. 2=2/1 /=divided by 1 and 2 only so is prime. if you don't know your multiples then count the amount e.g. 5 so count every 5 7 so count every 7 and so on

hope i helped -Kevin mcclay yr 9 st annes academy Langley genius 2012 :D