Correct Answer: 9
Explanation:
Let N = 312 x 28 ⇒ log N = 12 x log3 + 8 x log 2 ⇒ log N = 12 x 0.47712 + 8 x 0.30103 ⇒ log N = 8.13368 ∴ No.of digits = 8 + 1 = 9