Each of the first eight prime numbers is placed in a bowl. Two primes are drawn without replacement. What is the probability, expressed as a common fraction, that the sum of the two numbers drawn is a prime number?
+36916 2 3 5 7 11 13 17 19
there are 8 x 7/2 = 28 combos
here are some possibles 2 3 = 5
2 5 = 7
2 11 = 13
2 17 = 19
I don't think there are any more.....can you find any more? 4 out of 28
