The number of ways in which Kristen can rank her favorite four from 8 using permutations is 1680.
The permutation is a way of finding the number of ways of selecting a set of articles from a larger set of articles, with the order of selection being significant.
If we want to choose r items from n items, where the order of selection is significant, then we can find the number of ways of doing this using the permutation as follows:
nPr = n!/{(n - r)!}.
In the question, we are asked to find the number of ways Kristen can rank her favorite four investments from the 8 potential investments that her financial advisor has given her.
Thus, using permutations, we need to select 4 items from 8 items, with order of selection being significant.
Substituting n = 8, and r = 4 in the formula, we get:
8P4 = 8!/{(8 - 4)!}
= 8!/4!
= 5 * 6 * 7 * 8
= 1680.
Thus, the number of ways in which Kristen can rank her favorite four from 8 using permutations is 1680.
Learn more about permutations at
https://brainly.com/question/12468032
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