00:01
Hello! so breaking this down, looking at the four letters, well, if they're not case sensitive, so only a capital a through z, then we have 26 possible letters for each position, and we have the possibilities for four letters would then be, well, 26 and then times 26 times 26 times 26, so 26 to the fourth power, which works out to be a 456 ,976.
00:29
Now, if the letters are case sensitive, in other words, like, right, little a through z is going to be different from a through z, we have 52 possible letters for each position, the 26 lowercase and 26 uppercase, so then we're looking at 52 times 52 times 52 times 52, which is going to be equal to 7 ,311 ,616.
01:01
Now, for two digits, there's 10 possible outcomes, 0 through 9, for each position, so the number of different possibilities for two digits is just going to be 10 times 10, or 100, and then combining the letters and digits, so if they're not case sensitive, so, right, so not case, we have the total passwords for the letters is going to be 456 ,976 and then times 100 for the digits, so that's going to be equal to 45 ,697 ,600...
