You need to create a four digit code. You can use the digits 0 through 5. The first digit cannot be zero, and the digits are not allowed to repeat. How many such codes are possible?

mrs putzman has a briefcase with a three digit combination lock. she can set the combination herself, and her favourite digits are 1,2,4,5,7, and 8. each digit can be used at most once.  how many of the three digit numbers are even numbers and do not begin with 2

A math teacher asks each student to create a password to gain access to her website. The password has 5 digits. She makes up some rules for the students to follow in their password selection. The first digit must be a multiple of 1. The second digit must be a multiple of 2. The third digit must be a multiple of 3, and so on. How many possible passwords are there?

Solve step by step in digital formatXXXXXXXXXXXXXXXXXXXXX3. How many different five-digit numbers can be formed using only the digits of the number 75, 226, 522? Hint: consider numbers with one 2 first, then two 2, etc.