SOLUTION: You pick 5 digits (0-9) at random without replacement, and write them in the order picked. What is the probability that you have written the first 5 digits of your phone number?

Algebra ->  Statistics  -> Normal-probability -> SOLUTION: You pick 5 digits (0-9) at random without replacement, and write them in the order picked. What is the probability that you have written the first 5 digits of your phone number?      Log On


   

Question 1156562: You pick 5 digits (0-9) at random without replacement, and write them in the order picked.
What is the probability that you have written the first 5 digits of your phone number? Assume there are no repeats of digits in your phone number.
Give answer as a fraction.
Answer by greenestamps(13195) About Me  (Show Source):
You can put this solution on YOUR website!


P(first digit is correct) = 1/10

P(second digit is correct) = 1/9 (it has to match the second of your phone number; and it can't be the same as the first digit)

P(third digit is correct) = (1/8 (similar reasoning...)

etc....

P = (1/10)(1/9)(1/8)(1/7)(1/6) = 1/30240