There are ten cards.
One of odd numbers from 1 to 19 is written on each card.
When taking out two cards in order four times, each sum was 16, 18, 24, and 34 in order.
Find the numbers of the 2nd set and the 3rd set, respectively.
Answer
The 2nd set : 1 and 17,
The 3rd set : 11 and 13
Solution
4th set = 34 ＝15＋19
1st = (3,13), (5,11), (7,9)
2nd = (1,17), (5,13), (7,11)
3rd = (7,17), (11,13)
Above all, possible combination is 2nd(1,17) and 3rd(11,13).
