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6. Simplify the following expressions: a ) b ) (n+1)1 (n-1)! 7. Solve the following equations: a ) (n+1)! - = 15 b ) (n+2)! = 12 n! n! 8. Find the number of permutations of the letters in the word KITCHEN. a) No restrictions b) The number of permutations where the letters K I T must be together. 9 Student council is composed of 4 males and 7 females. How many ways can a 5-person subcommittee be chosen if: a ) 2 males and 3 females must be on the subcommittee? b ) At least one female must be on the subcommittee