candytrickster3951 candytrickster3951 02-01-2024 Mathematics contestada How many strings over the alphabet {a,b,c,d,e} have length 15 and exactly six b's? a) C(15,6)⋅9^5 b) C(15,6)⋅9^4 c) C(15,6)⋅4^9 d) C(15,6)⋅5^9
