SOLUTION: You are generating pin codes for ATM cards. Each pin code has 5 places, and each place can be a small letter or a number between 0 and 9. No letter or number can be used more tha

Algebra ->  Probability-and-statistics -> SOLUTION: You are generating pin codes for ATM cards. Each pin code has 5 places, and each place can be a small letter or a number between 0 and 9. No letter or number can be used more tha      Log On


   



Question 311230: You are generating pin codes for ATM cards. Each pin code has 5 places, and each place can be a small letter or a number between 0 and 9. No letter or number can be used more than once. How many different codes are there?
a) _10_ * _9_ * _8_ * _26_ * _25_ c) 26! + 10!
b) _36_ * _35_ * _34_ * _33_ * _32_ d) _35_ * _34_ * _33_ * _32_ * _31_
I thought the answer was d but i got it wrong can you explain why?

Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Your first place choice is out of 26 letters+10 numbers=36 total.
Then the second place is out of 35, since you cannot use the one you already chose.
Third, out of 34.
Fourth, out of 33.
Fifth, out of 32.
N=36%2A35%2A34%2A33%2A32
b) is the correct answer.