Answer:
336
Step-by-step explanation:
To define whether we use permutations or combinations we must define whether or not the order in which we arrange the results matters. If the order matters we use permutations and if the order doesn't matter we use combinations.
In this case, since we are talking about the first places in a competition, order definitely does matter, so we use permutations. Also in permutations it must be indicated if repetition is allowed, in this case not because the same person cannot be in more than one place.
We use the following formula:
where in this case n is the numer of swimmers and r is the number of places we are considering (1st 2nd and 3rd), which is 3 places.
n = 8
and
r = 3
thus the number of permutations is given bt:
the answer is that there are 336 ways in which the swimmers can finish in first second and third place