Lockbox
The
code to open a lockbox is made up of 5 different digits, from 1 to 5.
No digit can be placed next to its numerical neighbor.
(Example: 2 and 3 cannot be next to each other in the code.)
Question: Find the combinations that do not start with 4 or 5.
Answer:
These are 9 possible
combinations:
13524
14253
24135
24153
25314
31425
31524
35241
35142
