How can you get a four digit password using the numbers 0 through 9?

Answer 1

Turn the wheels to 0, then focus on the first wheel. 0000, 1000 ect.

Afterwards, the second wheel. 0100, 0200 ect.

Third wheel. 0010, 0020 ect.

Fourth wheel. 0001, 0002 ect.

First and second wheels. 1100, 1200, 2100 ect. (Do this by turning one wheel at a time. Makes it less confusing)

First and third wheels, 1010, 1020, 2010 ect.

First and fourth. 1001, 1002 2001 ect.

Second and third. 0110, 0120, 0210 ect.

Second and fourth. 0101, 0201 ect.

Third and fourth. 0011, 0021 ect.

First, second, third wheels. 1110, 1210, 1220, 2110 ect. (One at a time.)

First, second, fourth. 1101, 1102, 2201 ect.

First, third, fourth. 1011, 2011, 1202 ect.

Second, third, fourth. 0123, 0345 ect.

All. 1234, 2342, 3455, 4657, 9876 ect.