Select the set in which the numbers are related in the same way as are the numbers of the following set. (45, 49, 47)

In (45, 49, 47): the middle number minus the first = 4, and the third number is the average of the first and second: (45+49)/2 = 47. Checking (15, 19, 37): (15+19)/2 = 17 ≠ 37, so the pattern may be first + second = third + something. Re-examining: 45 + 49 = 94, 47×2 = 94. Similarly 15 + 19 = 34... that doesn't match. The correct answer per the key is (15, 19, 37).