Question

Permutations Question HELP!!!! In how many ways can 7 people be arranged in a line if X and another particular person Y are on neither end?

Answer 1

5 people in the middle can be arranged in 5! ways

Answer 2

and you can XY can be swapped in 2 ways

Answer 3

multiply both

Answer 4

oh its neither end ?

Answer 5

yeh its neither end

Answer 6

then just subtract these from total permutations 7!

Answer 7

X and Y on either end = 2x5!

X and Y on neither end = 7!-2x5!

Answer 8

thanks :D

Answer 9

yw !

Answer 10

I want you be aware that, this solution assumed the question was asking us to find number of permutations in which, X and Y are not SIMULTANEOUSLY on either end