Answer:
380
Explanation:
We have 20 choices for president. After that person is picked, there are 19 people to pick from for VP. There are 20*19 = 380 different permutations. Order matters because the two office positions are different.
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A slightly longer alternative is to use the nPr formula
where n = 20 is the number of people to pick from at the start, and r = 2 is the number of slots to fill. The exclamation marks refer to factorial notation.