Suppose that a natural number from 1 through 9 is selected at random. What is the probabiliy that the number selected is odd if you know that it is prime?

Question

Suppose that a natural number from 1 through 9 is selected at random.  What is the probabiliy that the number selected is odd if you know that it is prime?

SraJMcGin · Answer

Please identify the school subject so we know clearly what it is. Mat means nothing to me, but Math does. Sra

PsyDAG · Answer

The only prime numbers in that range are 1, 3, 5 and 7. They are all odd, 100%.

PsyDAG · Answer

Sorry, Assuming you count 1 as a prime number, and 9 is not. 4/5 = 80% If you don't count 1, it is 3/5 = 60%.