Correct Answer: 393
Explanation:
Ans. 4.5 = 7 x 0.5 + 1 5.5 = 4.5 x 1 + 1 12 = 5.5 x 2 + 1 49 = 12 x 4 + 1 ? = 49 x 8 + 1, i.e. ? = 393