Question

The access code for a card security system consist of four digits the first digit cannot be 4 and the last digit must be odd. How many different codes are avalible

Answer 1

Different codes for access code which are available are: 4000

_ _ _ _

1 2 3 4

1st blank can be filled with the following possibilities, here the conditions are:

1)The first digit cannot be 4

2)The first digit cannot be 0 also since it makes the access code 3 digits hence

From 1 to 9 except 4 there are  8 possible ways to fill that blank

8

2nd blank can be filled with any number between 0 to 9 in 10 possible ways

8 10

3rd blank can be filled with any number between 0 to 9 in 10 possible ways

8 10 10

4th blank can be filled with any odd numbers between 0 to 10 - 1,3,5,7,9

8 10 10 5 = 8 x 10 x 10 x 5 = 4000

Hence to conclude that 4000 available codes are there for the access security card

To know more about permutations and combinations please follow this link

brainly.com/question/1216161