SOLUTION: The sum of the digits of a number is 9. What is the probability that the number is prime?

Question 221110: The sum of the digits of a number is 9. What is the probability that the number is prime?
Found 2 solutions by stanbon, jim_thompson5910:
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
The sum of the digits of a number is 9. What is the probability that the number is prime?
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Answer: The probability is zero.
Why. When the sum of the digits is 9 the number is divisible by 9.
Try it and you will see.
Cheers,
Stan H.
Answer by jim_thompson5910(35256) (Show Source): You can put this solution on YOUR website!
Since "The sum of the digits of a number is 9", this means that the number is divisible by 9. So the chances that the number is prime is 0% (since 9 is a factor of this number).
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