No Zeros
Math brain teasers require computations to solve.
Can you find a five digit number which has no zeros and no digit is repeated, and where:
The first digit is a prime number.
The second digit is the fifth digit minus the first digit.
The third digit is twice the first digit.
The fourth digit is the third digit plus three.
The fifth digit is the difference between the first digit and the fourth digit.
Comments
cathalmccabe
May 23, 2002
 Excellent! 
bluetwo
May 23, 2002
 i enjoyed it! the key is working back to the second digit... i guess that could be a hint =) 
(user deleted)
May 23, 2002
 Thank you  that was a fun one! 
Mogmatt16
May 23, 2002
 fun, but easy, 
QtistLilShorTy
May 24, 2002
 it only took about 1 minute to figure out, but i enjoy problems such as these. You just use simple algebra to figure it out starting with the first number. You would do abcde(each letter to represent a number) and then put each into an equation. Again this is very simple, like 6th grade algebra. 
rohddawg
May 25, 2002
 Good Job... took some time and i do hate ppl that brag.. ya one minute my ass.. 
emmyluzam
Jun 01, 2002
 I agree with rohddawg, it took me 5 mins, noone can do it in 1 min! I h8 braggers! 
dumbdumb_smarts
Jun 03, 2002
 could 13254 work as well or is one not considered prime? Either way it was a fun one! 
librashorty
Jun 13, 2002
 thanks to everyone who thought it was good!! 
ymiroc
Jun 18, 2002
 To dumbdumb_smarts: yoiu are right about the number 1 not being prime. As a technicial matter, the smallest prime number is 2, and therefore the lead digit cannot be 1. good point though. 
mad_axeman
Jun 21, 2002
 I'm not very good at maths ones, but it took me about 10 minutes. It was a good one though. 
Dina_2002
Jun 21, 2002
 that was easy 
murkymerlin
Jun 21, 2002
 I just want to know how you got the inspiration to make this riddle!?
Anyway brilliant riddle, its going to my math teacher definitly! 
rahthree
Jun 21, 2002
 lol for whoever said one minute was impossible, it took me about 10 seconds. 
kkats4
Jun 21, 2002
 2 isn't a prime number. I'm going to 7th grade and we learned about these since 4th grade.

brainylana
Jun 22, 2002
 13254 is also an answer to that teaser...I'm pretty sure 1 is considered a prime number 
pemalova
Aug 21, 2002
 That was a nice one. Yeah, I choked, I misread a direction, but it was still good. 1 and 2 are both prime. 
xiaobaby
Aug 27, 2003
 yup. i took less than a minute but more than 10secs. maybe half a minute or so. its very simple. the first no., i took as A, could either be 2,3,5,7 but the C countered the last two cus twice of 5 was 10 and thats two digits. A and B, C and E, are 3 and 6. repeated. left me with only two digits (2,3) to solve from. 
xiaobaby
Aug 27, 2003
 2 is definitely prime, whoever who said is isn't. But 1 isn't. It old books, authors wrote that it was but most of today's textbooks states that 1 is neither prime nor composite. www.utm.edu 's list of prime numbers excludes 1. A prime number is defined as any number which can only be divided by its own and 1. 2's factors are 2 and 1 so its a prime number. 1 can be divided by 1 and its own, which is 1. Prime numbers have two factors and 1 only has 1. errr... something like that 
nuccha
Feb 27, 2005
 Yep. Quite sure 1 isn't prime and 2 is. To be prime you have to have 2 factors. to be composite you have to have more than 2. 1 fits in neither. about the problem, people weren't bragging they were just proud of an accomplishment i guess. fun and easy problem. good gap for the really lengthy ones. 
swetzel82
Apr 24, 2005
 i enjoyed this one. it was just a nice refresher. 
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