## Algebra 2 (1st Edition)

a) Using the Fundamental Counting Principle the number of possible choices is $26\cdot26\cdot10\cdot10\cdot10\cdot10\cdot10=67600000$ b) Using the Fundamental Counting Principle and the fact that the number of possible numbers/letters decreases by $1$ if we choose a number/letter, the number of possible choices is $26\cdot25\cdot10\cdot9\cdot8\cdot7\cdot6=19656000$