SOLUTION: What are the odds against choosing a prime number or a number divisible by 9 from 1 to 50

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Question 1026485: What are the odds against choosing a prime number or a number divisible by 9 from 1 to 50
Answer by robertb(5830) About Me  (Show Source):
You can put this solution on YOUR website!
There are 15 prime numbers between 1 and 50. There are 5 integers between 1 and 50 that are divisible by 9. This means there's a total of 20 of such numbers.
The odds against would be %2850+-+20%29%3A20+=+30%3A20, or 3:2.