Question

A realtor uses a lock box to store the keys to a house that is for sale. The access code for the lock box consists of digits. The first digit cannot be and the last digit must be . How many different codes are​ available? (Note that 0 is considered an even​ number.)

Answer 1

4,500 Codes

Explanation:

Given that, the access code consists of 4 digits.

Since, the First digit cannot be zero, and the last digit has to be even.

Therefore, Locks can only use numbers (0-9), which means the first digit has 9 possible outcomes ( 1-9),

the 2nd has 10 possible outcomes (0-10),

the same with the 3rd (0-10) and

finally the 4th has only 5 possible outcomes (0,2,4,6,8),

which we assume that zero is not excluded.

Finally, Mulitply 9 x 10 x 10 x 5 = 4,500.