SOLUTION: How many ordered sequences are possible that contain four objects chosen from thirteen

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Question 1114282: How many ordered sequences are possible that contain four objects chosen from thirteen
Answer by Edwin McCravy(20062) About Me  (Show Source):
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Pick the object to come 1st any of 13 ways.
That's 13 ways.
That leaves 12 unpicked objects to pick from.
Pick the object to come 2nd any of those 12 ways.
That's 13∙12 ways.
That leaves 11 unpicked objects to pick from.
Pick the object to come 3rd any of those 11 ways.
That's 13∙12∙11 ways.
That leaves 10 unpicked objects to pick from.
Pick the object to come 4th any of those 10 ways.
That's 13∙12∙11∙10 ways.

Answer: 13∙12∙11∙10 = 13P4 = 17160

Edwin