Solution:The pattern followed here is :[(2nd number × 6) - {(2nd number - 1st number) × 2}] = 3rd number
In (12, 13, 76) :- [(13 × 6) - {(13 - 12) × 2}] = 76
Similarly,
(15, 17, 98) → [(17 × 6) - {(17 - 15) × 2}] = 98
Hence, (15, 17, 98) is the correct answer.