At the school carnival, 50 sixth-grade, 30 seventh-grade, and 40 eighth-grade students bought tickets for the raffle. At the end of the night, Quincy draws out two names without replacement. What is the probability that she draws two-seventh-grade students? Please explain?

This is what i found “an explicit formula designates the nth term of the sequence, as an expression of n (where n = the term's location). it defines the sequence as a formula in terms of n. this example is an arithmetic sequence(the same number, 5, is added to each term to get to the next term).” i hope this you for what your looking for. can you plz mark me brainliest?