Question 1132038
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Any of the 5 letters in the first position. It gives you 5 options.


Any of the 4 remaining letters in the 2-nd position. It gives you 4 independent  options.


Any of the 3 remaining letter in the 3-rd position. It gives you 3 independent  options.


The total number of three-letters codes is the product 5*4*3 = 60.    <U>Answer</U>
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Solved.