a leader have chosen 8 boys out of a group of 12 boys. the leader drop out half of them and took the rest of them to a hall and put them in a straight line. How many different permutations are there for the boys in the hall?
Shouldn't it be 12c8×8c4×4! ?
Answer key: 7257600
#Help: Permutations :(
eternal elk
solemn zenithBOT
a leader have chosen 8 boys out of a group of 12 boys. the leader drop out half ...
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eternal elk
a leader have chosen 8 boys out of a group of 12 boys. the leader drop out half ...
Hmm
If the leader
Picks 8 and then 4
Don't u think it's just 12c4
(i might be wrong but this makes sense to me)
Like imagine a long series in which teacher picks 12 then 11 then 10 then 9... To 1
And puts that one student in hall
Would that change the combinations from 12 to whatever the large number u get
granite kiln
,w C(12 , 4)
keen coralBOT
keen coralBOT
granite kiln
@eternal elk Your logic was right we will overcount cases this way because Lets take example for smaller case of 4 ppl say A,B , C ,D if first 3 people ate selected say A , B , C
And then A is dropped we are left with B,C if B,C,D were selected and we drop D again B,C
So your answer is overcounting cases @eternal elk
So answer should be
,w C(12,4)*(4!)
keen coralBOT
eternal elk
So answer should be
It's weird that this doesn't match with answer key
granite kiln
It's weird that this doesn't match with answer key
The answer he said was in answer key equals to 10!*2
,w 10! * 2
keen coralBOT
granite kiln
This doesn't make any sense I think he saw the wrong answer in the answer key or answer key is wrong
eternal elk
The answer he said was in answer key equals to 10!*2
That's so random I mean it could be 72576*100
granite kiln
It's just a way to reverse engineer an answer while doing PnC 10! Is more likely to appear than 72576
eternal elk
It's just a way to reverse engineer an answer while doing PnC 10! Is more likely...
Still absurd that a 'wrong answer' would be derived with that calculation😅
eternal elk
This doesn't make any sense I think he saw the wrong answer in the answer key or...
You were right with this my dear friend, and the answer is right too, 11880, thank you buddy
@eternal elk Thank you too bro