there are 5 pairs of different style shoes. how many ways to choose 5 shoes that contains exactly one pair. noticing that left and right are distinguishable.
I feel like nCp and nPc or whatnot should be involved here but I haven't seen either of them in forever. They are like the long lost brothers of my math.
does the pair have to be a matching pair?
yes the pair should be matching
nvm, that's wrong
10*8*6*4*4
I'm just gonna mark that right because you know what you are doing. TAKE GOOD CARE OF MY BROTHERS.
start with 10 shoes after that you can only pick from 8 then 6 then 4 then 4 ways to pick the last matching shoe
assuming you are picking them all at the same time
sorry but i dont think its correct, the answer for 7 pairs shoes(nothing else changes) is 420...the answer i got from your way seems too large
sorry the question changes to choose 4 shoes from 7 pairs, and should have one matching pair
its right, for the seven one you start with 7 after that you can pick 5 then 3 then 1 then 4 to match the pair
so 7*5*3*1*4=420
i'm sorry because for the 7 case the question asked to choose 4 shoes from 7 pairs, not 5...i didn't see the question carefully...and 7 is the number of pairs, totally have 14 shoes with distinguishable left and right
its still the same: you start with 7 after that you can pick 5 then 3 then 4 to match the pair 7*5*3*4=420
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