Task 2. Angelica wants to choose a three-digit code for her suitcase. To make it easier to remember, Angelica wants all the digits in her code to be in non-decreasing order. How many different options does Angelica have for choosing the code?
Problem 678
Official solution
Problem 2. Angelica wants to choose a three-digit code for her suitcase. To make it easier to remember, Angelica wants all the digits in her code to be in non-decreasing order. How many different ways can Angelica choose her code? Answer. 220.