In a group of 10 people, there are 4 people that have the flu virus. Suppose we pick 3 random persons to test in order to determine if they have the flu and, to simplify our analysis, we suppose that the test is 100% accurate. Let X be the random variable consisting of the number of positive flu tests out of 3.

Tests is 100% Accurate, so by using the formula of random variable probability.

Step-by-step explanation:

Total number of people = 10

Sample space = p(A) = 10

Number of people that have flu = n(s) = 4

Pick random 3 persons, the possibility that they have flue is n(A) = ?

Let X is the random variable, consisting of number of positive flu test,

Tests is 100% Accurate, so by using the formula of random variable probability, we get

  P(X) = n (A) / n(S)

  P(X)      = ¾, is the probability of having positive flu test

d

step-by-step explanation:

hello and welcome!

so, when we see the words "proportional" along with a table, we need to know that we're looking numbers that divide by the same thing.

looking at this table, we simply have to do a trial and error, and divide to see which numbers have the same quotient. if you look at choice a & c, they both have equal quotients for three of the numbers, with one exception, so those can't be the answer. looking at b, there is no similarity, so that can't be it. then, we see d; if you divide all the numbers in the table, you'll see that they all divide by two, which is a proportional relationship, and our answer!

also, always remember that the x will always be the number that goes into y, and somewhere behind this table, is a formula. for this specific table, the formula would be:

since our x-value is being divided by two to get the y-value. and if they were to ask for more numbers in the series, this is the formula you would use to find them.