Probability of AP

Probability Level 4

Out of 10001 tickets numbered consecutively, 3 are drawn at random .

Find the chance that the numbers on them are in Arithmetic Progression .

The answer is of the form $\frac{l}{k}$ .

Find $k - l$ where $k$ and $l$ are co-prime integers.

HINT : You might consider solving for $2n + 1$ tickets .

You can try more of my Questions here .