The answer is -5x + 4y = -20
First, there are 26 distinct alphabets and 10 distinct digit numbers.
Then, the first digit of ID has 26 possibilities.
For the rest of 2 digits, the total cases are 10*10 = 100 possibilities.
However, there are 10 cases are repeated when two digits are the same. so you have to subtract it by 10
So answer will be 26 * (100-10) = 23400
Not enough information given
Given:
You scored 12, 8, 15, and 21 points during your first four basketball games.
To find"
The mean score per game.
Solution:
We have,
Observations =12, 8, 15, and 21 points
Number of observations = 4
We know that,

The mean score per game is



Therefore, the mean score per game is 14 points.