I have a set of numbers $\{1,2,3,...,157\}$.
How to compute the probability of selecting two numbers without replacement such that are both divisible by $3$?
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Sign up to join this communityI have a set of numbers $\{1,2,3,...,157\}$.
How to compute the probability of selecting two numbers without replacement such that are both divisible by $3$?
Multiples of $3$ in the given range are $3\times1 $ through $3\times52$, i.e. numbering $52$
Thus $Pr =$ $\dbinom{52}{2} \over \dbinom{157}{2} $