From 1, 2, 3 In 2008, take any two numbers, then the sum of the two numbers is the probability of even numbers

From 1, 2, 3 In 2008, take any two numbers, then the sum of the two numbers is the probability of even numbers

Odd 1004
Even number 1004
Sum is even, two odd or two even numbers
Probability = [C (21004) + C (21004)] / C (22008)