I know that it's super-easy, and that I should be able to get it no problem, but I just drew a blank! Okay, here's the question...
The PIN numbers for a cash card at a bank contain four digits 1-9. All codes are equally likely. Find the number of possible PIN numbers.
This is a question for the end-of-year test for a school in the Dominican Republic. It's the last question. No, I'm not cheating! I'm making the answer key, 'cause the guy who made the test didn't make an answer key!
2007-06-27 15:07:43 · 7 answers · asked by Seth R 2 in Science & Mathematics ➔ Mathematics
u r making the answer key? Its good you are not a doctor, so we can avoid coming to your practice.hehe, jk.
anyways,
there are 9*9*9*9 possible pin numbers, unless you are not allowed to repeat numbers, in which case it will be
9*8*7*6 possible pins.
EDIT: i guess you did not like me pulling your leg. I apologize.
2007-06-27 15:13:18 · answer #1 · answered by swd 6 · 0⤊ 1⤋
If only 1-9 are allowed then the number of possibilities is 9^4.
However if 0-9 are allowed, the then number is 10^4 = 10000
(That's 0-9999).
2007-06-27 15:11:44 · answer #2 · answered by rt11guru 6 · 1⤊ 0⤋
9 x 9 x 9 x 9 = 6561
If it was 1 - 9 with no repeats ( meaning no number twice)
it would be 9 x 8 x 7 x 6 = 3024 (fyi)
2007-06-27 15:11:56 · answer #3 · answered by Anonymous · 1⤊ 0⤋
9^4= 6561
2007-06-27 15:12:02 · answer #4 · answered by DBSII 3 · 0⤊ 0⤋
9^4 = 6561.
2007-06-27 15:11:17 · answer #5 · answered by Scarlet Manuka 7 · 1⤊ 0⤋
oops yeah I put 10 to the 4th originally. It is 9 to the 4th.
2007-06-27 15:11:35 · answer #6 · answered by JJ 2 · 1⤊ 1⤋
if you're not repeating numbers 9!4
or 9x8x7x6
2007-06-27 15:13:10 · answer #7 · answered by Chief High Commander, UAN 5 · 0⤊ 0⤋