



 
Hi Tricia. Just go through them in sequence: Likewise, As you can see, there are 24 in total. This is because there are four choices for the first digit, then once that is chosen, there are three remaining choices for the second digit, then two for the third and whatever is left over must be the fourth digit. So that is four choices times three choices times two choices times one choice. 4 x 3 x 2 x 1 = 24. Twenty four attempts to open your lock won't take long.  


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