Question

A secret code consist of 3 digits from 0 to 9 followed by 2 letters from ’A’ to ’Z’. None of the digits or letters repeat. How many secret codes are possible?

Answer 1

Total number of possible secrets = 468,000

Explanation:

total number of places are 5 . out of which 3 places are filled by 10 numbers from 0 to 9 which cannot be repeated therefore

number of choice of filling first place for a number is 10

number of choices of filling second place is 9

number of choices of filing third place is 8

number of choice of filling letters at first place of alphabet = 26

number of choices of filling letters at second place of alphabet =25

therefore total number of possible codes = 10x9x8x26x25

=468,000