Answer : 1. "8640"
Explanation :

Answer: A) 8640 Explanation: Let the 6 digits of the required 6 digit number be abcdef Then, the number to be odd number the last digit must be odd digit i.e 3, 5, 7 or 9 The first digit cannot be ‘0’ => possible digits = 3, 5, 7, 2, 6, 8 Remaining 4 places can be of 6 x 5 x 4 x 3 ways This can be easily understood by Therefore, required number of ways = 6 x 6 x 5 x 4 x 3 x 4 = 36 x 20 x 12 = 720 x 12 = 8640 ways.