Determine the number of pairs of candidates in each of the following elections. An election with 7 candidates and 200 voters.

Welcome to the practice. In this problem, we'd like to determine the number of pairs of candidates in each of the following elections. First, we have an election with 7 candidates and 200 voters. Our formula to find the number of pairs so that the number of pairs is going to equal the Number of candidates times the number of candidates minus 1 divided by 2. We actually don't need the number of voters at all, so let's cross out that extra information. We can see here that the number of candidates is 7, so N here is going to be equal to 7. Let's plug everything in. So we have that C, our number of pairs of candidates, will be equal to 7 times 7 minus 1 divided by 2. This is 7 x 6 divided by 2, and 7 times 6 is 42. So this is 42 divided by 2, which is 21. So we have 21 pairs of candidates. Now, another way to do this, if you don't want to use the formula, is to come up with names for the 7 candidates, even something as simple as A, B, C, D, E, F, and G. Once you have the names, then just pair them up. Start with the first candidate on the list and pair them with everyone below them. Then the second candidate and pair them with everyone below them, and so on and so forth until you get to the final pair. Then you can just count your pairs. No matter which method you use, you will end up getting 21 pairs of candidates. As we start getting to more candidates, I will say the formula method is typically easier. Great work.

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Determine the number of pairs of candidates in each of the following elections.An election with 7 candidates and 200 voters.

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Determine the number of pairs of candidates in each of the following elections.
An election with 7 candidates and 200 voters.