How many different three-digit numbers can be made from the digits 6, 8, and 9 if each digit appears only once in the arrangement?

[1] 2 [2] 6 [3] 12 [4] 120

Question

How many different three-digit numbers can be made from the digits 6, 8, and 9 if each digit appears only once in the arrangement?

       [1]  2                        [2] 6                       [3]  12                      [4]  120

anonymous · Answer

To make 3 digit numbers from these, you basically have three slots to fill.  For the first slot, you have 3 choices, for the second slot you have 2 choices (since you used one already for the first slot), then for the third slot you have 1 choice.  The total number of choices is found by multiplying these three numbers: 3*2*1=6

anonymous · Answer

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Here's a crude drawing of the different branching choices.  Each slot you pick creates more branches, so that's why you multiply the number of choices for each slot.