What is the probability that a randomly chosen positive factor of 72 is less than 10?
and
A list consists of all possible three-letter arrangements formed by using the letters A, B, C, D, E, F, G, H such that the first letter is D and either the second or third letter is A. If no letter is used more than once in an arrangement and one three-letter arrangement is randomly selected from the list, what is the probability that the arrangement selected will be DCA?

Problem 1

S = sample space = set of all possible outcomes

S = set of positive factors of 72

S = {1,2,3,4,6,8,9,12,18,24,36,72}

n(S) = number of items in sample space

n(S) = 12

E = event space = set of outcomes we want to happen

E = set of factors of 72 such that they are less than 10

E = {1,2,3,4,6,8,9}

n(S) = number of items in event space

n(S) = 7

P(E) = probability get a value in set E (that is also in set S as well)

P(E) = probability we get a positive factor of 72 that is less than 10

P(E) = n(E)/n(S)

P(E) = 7/12

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Problem 2

n(S) = 12

E = event space

E = {DCA}

n(E) = 1

P(E) = probability we get an item in set S that is in set E also

P(E) = probability we get DCA from set S listed above

P(E) = n(E)/n(S)

P(E) = 1/12

the distance from any point on the parabola to the focus is the exact same as the distance from that point to the directrix.

if you could provide answer choices that might allow me to answer the question easier if my above answer isn't an option! (:

step-by-step explanation:

bob the banana