Respuesta :
Answer:
90
Step-by-step explanation:
base in my previous learning.. hope it helps
Answer: 90 different ways
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Explanation:
We have 10 ways to pick the first place finisher, and then 10-1 = 9 ways to pick the runner in second. Therefore, 10*9 = 90 different ways.
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The longer method you can use is to apply the nPr permutation formula which is
[tex]_nP_r = \frac{n!}{(n-r)!}[/tex]
where in this case, n = 10 and r = 2. The exclamation marks indicate factorial. A permutation is used since order matters.
