At Least Two Digits Alike
Difficulty: Easy · Topics: Discrete Mathematics, Counting Principle
A=\0,1,2,3,4,5\
Using elements of A (digits may repeat), how many three-digit natural numbers have at least two equal digits?
Difficulty: Easy · Topics: Discrete Mathematics, Counting Principle
A=\0,1,2,3,4,5\
Using elements of A (digits may repeat), how many three-digit natural numbers have at least two equal digits?