SOLUTION: find the number of permutations. 12 as a base of P and 5 as a base also.

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Question 194351: find the number of permutations. 12 as a base of P and 5 as a base also.
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
n%21%2F%28n-r%29%21 Start with the permuation formula



12%21%2F%2812-5%29%21 Plug in n=12 and r=5



12%21%2F7%21 Subtract 12-5 to get 7



Expand 12!
%2812%2A11%2A10%2A9%2A8%2A7%2A6%2A5%2A4%2A3%2A2%2A1%29%2F7%21



Expand 7!
%2812%2A11%2A10%2A9%2A8%2A7%2A6%2A5%2A4%2A3%2A2%2A1%29%2F%287%2A6%2A5%2A4%2A3%2A2%2A1%29



Cancel



12%2A11%2A10%2A9%2A8 Simplify




95040 Now multiply 12*11*10*9*8 to get 95,040


So 12 choose 5 (where order does matter) yields 95,040 unique permutations