I'm not positive if this is the right place for this(not certain if it's "pre-university" level or not) but my question has to do with rolling dice and getting at least a certain number, in a certain order.

Best way to ask this I think, is to give my primary example. These rolls are made using standard 6 sided dice(in a magical world where no bias exists in the dice).

3d6 roll #1: needs to result in a sum of all rolls equal to 8 or more(83.80% chance)

3d6 roll #2: needs to result in a sum of all rolls equal to 4 or more(99.54% chance)

3d6 roll #3: needs to result in a sum of all rolls equal to 11 or more(50% chance)

3d6 roll #4: needs to result in a sum of all rolls equal to 3 or more(100% chance)

3d6 roll #5: needs to result in a sum of all rolls equal to 3 or more(100% chance)

3d6 roll #6: needs to result in a sum of all rolls equal to 4 or more(99.54% chance)

The order of the rolls IS important. If someone could tell me(and possibly explain) the formula for figuring out the percentage chance for the rolls succeeding in this order, I'd be very thankful.