Question

1. how many 4-digit passcodes can be created if each digit can be any number, 0-9?

40
6,561
10,000
5,040

Explanation:

Step1: Identify digit choices

Each digit (thousands, hundreds, tens, ones place) can be 0 - 9, so 10 choices per digit.

Step2: Apply multiplication principle

For a 4 - digit passcode, the total number of passcodes is \(10\times10\times10\times10\) (since each of the 4 positions has 10 options).
Calculate \(10^4 = 10000\).

Answer:

10,000 (the option with "10,000")