SOLUTION: You have just been assigned a random 4-digit password made up of digits from 0 to 9. What is the probability that your password starts with a 3? Repetition is not allowed.

Algebra.Com
Question 1196823: You have just been assigned a random 4-digit password made up of digits from 0 to 9. What is the probability that your password starts with a 3? Repetition is not allowed.
Found 2 solutions by ikleyn, greenestamps:
Answer by ikleyn(52778)   (Show Source): You can put this solution on YOUR website!
.

The probability is  P =  = .     ANSWER


In the fraction, the denominator is the number of all allowed 4-digit passwords with no repetition;

                 the numerator is the number of those passwords that start with a "3".

Solved.



Answer by greenestamps(13198)   (Show Source): You can put this solution on YOUR website!


Without restrictions, there are 10 possibilities for the first digit.

With the restriction, there is only 1 possibility: the first digit must be 3.

So the probability that the first digit is 3 is 1/10.

And after the first digit there are no further restrictions; the probability is 1 that the last three digits satisfy the conditions.

ANSWER: (1/10)*1 = 1/10
RELATED QUESTIONS

You have just been assigned a random 4-digit password made up of digits from 0 to 9. What (answered by ikleyn)
You have just been assigned a random 3-digit password made up of digits from 0 to 9. What (answered by Boreal)
A hacker is trying to guess someone's password. The hacker knows (somehow) that the... (answered by Boreal,ikleyn)
Consider all four-digit numbers that can be made from the digits 0-9 (assume that numbers (answered by ikleyn)
6 digit passwords are randomly assigned to students by the computer department when they... (answered by jorel1380)
please help me solve this problem. a computer password made up of four characters. Each... (answered by Fombitz)
what is the probability of winning a lottery game where the winning number is made up of... (answered by stanbon)
What is the probability of winning a lottery game where the winning number is made up of... (answered by jim_thompson5910)
A hacker is trying to guess someone's password. The hacker knows (somehow) that the... (answered by ikleyn)