We have 12 letters- 4 A's 3 B's 2 C's and D,E&F The are to be arranged in a row such that the C's are separated from one another. The total number of ways this can be done is-
the rest of the letters might as well be all the same ....
12 spots, 2 cs, and need to be separte
cxcxxxxxxxxx cxxcxxxxxxxx .... there are 9 of those :) move over by 1 xcxcxxxxxxx tthere are 8 of those 9+8+7+6 .... is what im thinking
err, starts with 10 ways eh
_A_A_A_A_B_B_B_D_E_F_ the As Bs and D,E,F can be arranged in \[\frac{10!}{4!*3!}\] ways...(1) now we can fill 12 remaining spots with 3Cs.....is 12C3 ways.....(2) multiply (1)(2)
sorry (2) its in 12C2 ways...
my idea takes me too: 10(10 + 1)/2 = 5(11) = 55 ways ....
answer in the book is 1386000 ... I'm not quite getting there
im of course ignoring that some letters are positioned in other manners, so it prolly a bit low lol
number of different ways to arrange the nonC letter ... times 55 ways to put in the cs afterwards ... maybe
you can also try solving like this : 1) find total number of ways of arranging the given 12 letters 2) find total number of ways of arranging 12 letters such that 2Cs are together 3) subtract 2 from 1
1) 12! / 4!3!2! 2) 11! / 4!3! 3) ?
\[\frac{n}{a!b!c!...}\]
\[\frac{10!}{4!3!2!}*55\] lets see if the wolf likes it lol
693 000 aint what the book says, so ugh!!
@amistre64 logic is correct... its \(\frac{10!}{4!3!}*55\) 2! shouldnt be there in the bottom as we fixed c's to start with !!
@amistre64 u should remove the 2!....in the denominator...
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