How To Find Prime Numbers: The Sieve of Eratosthenese

[badman98ish]

u missed the 6 put on the 3 x

[angelajoyx3]

I mean 2

[angelajoyx3]

I had to watch I 2 times but know I got it thak you soo much

[sz42781]

fml

[bubbleboy2001]

6 is a multiple of 3 and 45 is not a multiple of 3.

[bloodbutter4]

45 is divisible by 3. 45 / 3 = 15 A quick way to check if something is divisible by three is to add all the digits in the number together and see if that sum is divisible by three. 4 + 5 = 9, 9 / 3 = an integer; therefore, 45 is divisible by 3.

[rawr7654]

@bubbleboy2001 3 x 15 = 45 so 45 is a multiple of 3... wow, lol

[kradrumble]

thank you so much ill be done my homework in no yime

[JEThorburnJr]

Cool demo. Please change the spelling of the Greek philosopher's name to ERATOSTHENES. The pronounciation is AIR-UH-TOS-THEN-EES.

[VaginosaurusRex]

add up the digits and see if its evenly divisible by 3. if it is not evenly divisible by 3, it IS prime. If it is evenly divisible by 3, it is NOT prime. examples: "59" 5+9=14. 14 isnt evenly divisible by 3, 59 is prime. "57" 5+7=12. 12 IS evenly divisible by 3, so it is NOT prime. hope this helps :)

[shahz2011]

thankyou soooo much i cant understand any other wikipedia ways or anything but you just simplified it!!! subscribe!

[toddlusk]

@MagicMasterable You're very welcome. :-)

[MagicMasterable]

thankyou sooo much!!

[weasel13ocsa1]

luv it

[AndyHarglesis]

It's good to know prime numbers like me, but overall they do no justice in a lot of day-to-day work.

[wordpimp2787]

i never heard of this i was always thought doing it the "tree branch" way which is more complicated but this is way easyer thanks

[binasheikh1974]

Pls help. How can I teach my daughter if a larger number say 599 is a prime number or not. Thanks.

[cucicuci18]

thanks bro.

[2fartyfart]

this helped me finish my homework due tomorrow thanks! :) but i have to find all prime numbers less than 100 so i think i can do tht now! :D

[weasel13ocsa1]

@2fartyfart me 2

[ekjvbihr]

i will thanks

[ekjvbihr]

u legend this helped me with my homework due tomorrow thanks

[toddlusk]

Glad that it helped. Show your teacher how it works.