Question

How many combinations are possible on a 4 number bicycle lock?  Each space can be any digit 0 - 9.  The only exception is that all four numbers cannot be the same.

Answer 1

There are 23 possible combinations on a 4 number bicycle lock, excluding the combination where all four numbers are the same.

Step-by-step explanation:

There are 10 possible digits that can be used for each space on the bicycle lock, ranging from 0 to 9. Since there are 4 spaces, we can calculate the number of possible combinations by finding the factorial of 4, denoted as 4!. This is calculated as 4 x 3 x 2 x 1 = 24.

However, we need to subtract the combination where all four numbers are the same, so the final number of combinations is 24 - 1 = 23.