

Stephen Buxton Veteran user 311 Posts 
Using all the digits from one to nine only once, make up three numbers of three digits each. Add these three numbers together to give you an answer.
There are a lot of possible answers you can get  how many of these are prime?
If you put an infinite number of apes in front of an infinite number of computers, you get a pretty good idea of what internet chat rooms can be like

Sapient Regular user 126 Posts 
None are prime. This can be demonstrated with a simple mental exercise that will amaze us all.
At least that is what I am guessing. 
TomasB Inner circle Sweden 1143 Posts 
If a digital root of a number is 9, it is dividable by 9, so no matter how you arrange and sum up the digits from 1 to 9 (1+2+...+9 has a digital root of 9) you always get a number dividable by 9.
Sapient got it. /Tomas 
Stephen Buxton Veteran user 311 Posts 
Indeed he did! Well done, all
If you put an infinite number of apes in front of an infinite number of computers, you get a pretty good idea of what internet chat rooms can be like

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