Counting & ProbabilityChallengeCounting & Probability ShareCounting & Probability · Challenge problemHow many permutations a1a2⋯a9a_1a_2\cdots a_9a1a2⋯a9 of {1,2,…,9}\{1,2,\dots,9\}{1,2,…,9} satisfy a1<a2<a3<a4<a5a_1<a_2<a_3<a_4<a_5a1<a2<a3<a4<a5 and a5>a6>a7>a8>a9a_5>a_6>a_7>a_8>a_9a5>a6>a7>a8>a9?Check Show answer Walk through it step by step Practice more like this Review this concept