Find the number of permutations of the first 12 letters taken 3 at a time ?

Question

anonymous · Answer

@dan815 @triciaal

anonymous · Answer

@Hero

triciaal · Answer

12P3 = 12!/(3!9!)

anonymous · Answer

1320

anonymous · Answer

@triciaal In how many ways can a teacher arrange 10 students in the front row if there are 60 total students?

triciaal · Answer

* correction we do not divide when it is not specific

anonymous · Answer

@triciaal so 1320 isnt the correct answer?

triciaal · Answer

permutations and combinations  the possible arrangements and specific arrangement

anonymous · Answer

i dont understand what you mean @triciaal

triciaal · Answer

how many ways can you choose 3  starting with 12 
12 * 11* 10 = 1320

anonymous · Answer

alright so i got it correct @triciaal

anonymous · Answer

@triciaal In how many ways can a teacher arrange 10 students in the front row if there are 60 total students?

triciaal · Answer

now I think we divide 
there are 6 groups of 10 for 60 but the combinations are important 
once a particular student is chosen then no longer in the "pool" to be chosen for the front row

anonymous · Answer

nPr= 60!/(60-10)!

triciaal · Answer

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not sure 
do you have the choices ?