MovieChat Forums > Weakest Link (2001) Discussion > prime number question

prime number question

posted 20 years ago by KAnnD86
7 replies | jump to latest

okay, this obviously wasn't the right place to come since no one has posted anything here, but i'll try anyway just in case. i am watching a rerun of the weakest link on game show network and it's the episode with celebrities like kathy griffin and rob schneider and the guy from fear factor and aisha tyler. she just asked a question "which of these is a prime number: 31 or 51?" aren't they both prime numbers? please, correct me if i'm wrong. they ended up saying that 31 one was the prime number but 51 is definitely also a prime number. i'm just a little confused. did i misunderstand?

[–] Im_A_Cop_You_Idiot 20 years ago

they are right 51 is not prime

51 is divisible by 1, 3, 17, and 51.

31 is only divisible by itself and 1, making it prime.

[–] KAnnD86 20 years ago

Thanks. Somebody already PMed me and told me that. I don't know why i didn't figure that out. I tried doing the math and everything. Guess I was just too lazy to get to 17. LoL. Also, I went online and searched for lists of prime numbers and I swear 51 was on one. Oh well. Thanks for clearing that up for me. :)

[–] caguitar2001 19 years ago

just follow this rule to test a prime.. if the number is even or ends in 5 (except for 5) then its not prime. then if the number cannot be divided by 3 7 or 9 then its a prime...

[–] SDockorockerty 19 years ago

ok.....

[–] 19 years ago

[deleted]

[–] danlibbo 18 years ago

"Guess I was just too lazy to get to 17"

hahaha - or 3 - that's a pretty bad test for primeness

[–] 18 years ago

[deleted]