Answer:
9,945,936,000.
Step-by-step explanation:
This is the number of permutations of 6 letters from 26 multiplied by number of permutations of 3 odd digits between 0 and 9.
The total number of odd digits between 0 and 9 are 1,3,5,7,9 = 5.
So the number of choices are
26P6 * 5P3.
= 26!/(26-6)! * 5!/ 2!
= 26!/20! * 5!/2!
= 165765600 * 60
= 9945936000.