We have $100$ slots each of which are picked with equal probability by the hash function (since hashing is uniform). So, to avoid first $3$ slots, the hash function has to pick from the remaining $97$ slots. And repetition is allowed, since chaining is used- meaning a list of elements are stored in a slot and not a single element.
So, required probability $= \frac{97}{100} \times \frac{97}{100} \times \frac{97}{100}$
$= (97 \times 97 \times 97)/100^3$