Question

The access code for a cars security system consists of 4 digits. The first digit cannot

be 0 and the last digit nust be even. How many different codes are available?

Answer 1

4500

Explanation:

The first digit can't be 0. so it will be a number from 1000 to 9999. That's a total of 9000 numbers (9999-1000+1=9000). Since the last digit must be an even number that is one half of the 9000 numbers which is 4500.