20-05-2023

Problem: A word is a string of letters drawn from the $26$ English alphabets $a,b,\dots,z$. Let $n$ be any natural number.

  • How many words are there of length $n$?
  • How many words are there of length $n$, with exactly three $b$'s?
  • How many words are there of length $n$, with no vowels?

Solution: I encourage you to attempt to solve the problem today. The solution will be provided tomorrow. This will give you the opportunity to test your understanding of the problem and to improve your skills in solving similar problems in the future.