There are 20 entries in the chess tournament. how many ways can they finish in first, second,
and third place?

6840

Step-by-step explanation:

Here, the order matters (1st, 2nd, and 3rd), so we need to use permutations.

There are 20 people who can get in first place.  After that, there are 19 people who can get in second place.  Finally, there are 18 people who can get in third place.  So:

20 * 19 * 18 = 6840

the correct answer is the second option

let m = monomial

let t = trinomial

so, m times t = t.

monomial times a trinomial = another trinomial.