Question 25
In how many ways can the letters of the word COMBINATORICS be arranged so that the letters $C$, $O$, $A$, $C$, $T$, $O$, $R$, $S$ appear in that order in the arrangement (although there may be letters in between)?
Math Olympiad Vault · MathNet 2018-part-04 — 181 problems (EN–VI)