As repetition is not allowed total no. of cases possible is 9 × 8 × 7(because if one of the numbers occupies a wheel, then the other wheel cannot be occupied by this number, i.e. next wheel have 1 less case than the previous wheel and so on)
Therefore, total cases = 504
Desired output is the correct combination of a single 3 digit number.
Therefore, the total no. of desired outcomes are 1
We know that,
Probability of occurrence of an event
= \(\frac{Total\,no.of\,Desired\,outcomes}{Total\,no.of\,outcomes}\)
Therefore, the probability of correct combination
= \(\frac{1}{504}\)
Conclusion: Probability of guessing right combination is \(\frac{1}{504}\)
