There are 7 balls
which are branded with the numbers like 1,2,3,4,5,6,7 and
each one of them has the same value of the branded number suggests.
These balls are gathered in a sack.
Jack takes 3 of these balls and says Janet that whatever 2 balls she pulls, the sum of them is gonna be an even number. What is the sum of 3 balls' value that Jack is holding?