In how many ways can 15 students be seated in a row so that 2 most talkative children never sit together.
A 14! 14!
B 15.14!'
C 14!
D 14!.13
E 15!
Shouldnt the answer be 14.14!
I mean 15 students can be arranged in 15! ways and assuming that 2 most talkative always sit together. 14! ways, hence the ways in which they never sit together 15!-14! = 14! (15-1) = 14.14!. What am i doing wrong?
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Neo2000
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Total number of ways = 15!
Consider the 2kids as 1 unit, they can now be arranged in 14! x 2! since the two kids can be arranged among themselves in 2! ways
Hence answer = [spoiler]13.14![/spoiler]
Consider the 2kids as 1 unit, they can now be arranged in 14! x 2! since the two kids can be arranged among themselves in 2! ways
Hence answer = [spoiler]13.14![/spoiler]
