How many different ways are possible to arrange the letters of the word MACHINE so that the vowels may occupy only the odd positions?
notice all letters in \(MACHINE\) are unique. let's write out a possible "blank slate":|dw:1389858937936:dw|
a,i e occupies position 1,3,5,7 so 4p3=12ways
the 1st, 3rd, 5th, and 7th positions will be occupied by the consonants while the 2nd, 4th, and 6th will be occupied by the vowels
only vowels occupy odd positions
oh oops I misread!
you suck haha
4!*3! total
24*6=144 ways
you suck more hahaha
actually \(_4P_1=4!/(4-1)!=4!/3!=4\) i.e. \(4\) ways to pick the \(3\) odd spots for vowels... anyways now we just fill in the others. we count the consonants separately (just fill in the even spots and the one unoccupied odd spot) so \(4!\)... there are also \(3!\) ways to assign the vowels to the \(3\) spots we picked so our answer is just \(4\cdot4!\cdot3!=576\)
how
4 how
yeah
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