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Question from Mike, a parent:

How many combinations of this four digit number 1028 can this produce only using those numbers. Example would be 0000, 0001,0002,0008,0010,0011,0012,0018,etc...

Hi Mike,

How many combinations of this four digit number 1028 can this produce only using one those numbers.

Answer: 4. They are 1, 0, 2 and 8.

How many combinations of this four digit number 1028 can this produce only using two those numbers.

Answer: 4 × 4 = 16. Each of the 1 digit numbers you can extend to a 2 digit number in 4 ways,

11, 10, 12, 18
01, 00, 02, 08
21, 20, 22, 28
81, 80, 82, 88

How many combinations of this four digit number 1028 can this produce only using three those numbers.

How many combinations of this four digit number 1028 can this produce only using four those numbers.

I hope this helps,
Penny

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