大家好，小女子求一道GWD的数学解析，谢谢！！

karmen8000

Each participant in a certain study was assigned a sequence of 3 different letters from the set {A, B, C, D, E, F, G, H}. If no sequence was assigned to more than one participant and if 36 of the possible sequences were not assigned, what was the number of participants in the study? (Note, for example, that the sequence A, B, C is different from the sequence C, B, A.)
(A)20

(B)92

√(C)300

(D)372

(E)476

dliu64

这个题就是问从八个不同letters 里面取3个letters 有多少种取得发。 就是336咯。。 然后题目里告诉你有36个不能Assigned.所以就是336-36=300