SOLUTION: Student ID codes consist of uppercase letters as well as the digits 0 through 9. How many 2-character ID codes are possible if at least one of the digits must be a number?

Algebra ->  Permutations -> SOLUTION: Student ID codes consist of uppercase letters as well as the digits 0 through 9. How many 2-character ID codes are possible if at least one of the digits must be a number?       Log On


   

Question 610198: Student ID codes consist of uppercase letters as well as the digits 0 through 9.
How many 2-character ID codes are possible if at least one of the digits must be a number?
Found 2 solutions by Alan3354, sudhanshu_kmr:
Answer by Alan3354(69443) About Me  (Show Source):
Answer by sudhanshu_kmr(1152) About Me  (Show Source):
You can put this solution on YOUR website!
Case 1: Both digits are numbers.

Number of possible ID codes = 10^2 = 100 ( 00,01,.... to 99)
Case 2: First digit is number and second is a letter.
Number of possible ID codes = 10*26 = 260 [ ex- 9A, 8D,. ]
Case 3: First digit is letter and second is a number.
Number of possible ID codes = 26*10 = 260 [ ex- A6, D7,. ]

Total number of possible ID codes = 100+ 260 +260 = 620

If any doubt, feel free to contact my mail. sudhanshu.cochin@gmail.com