Mathematics, 25.05.2021 07:00 zazy15

Mr. and Mrs. Doran have a genetic history such that the probability that a child being born to them with a certain trait is 0.8. If they have three children, what is the probability that exactly two of their three children will have that trait? Round your answer to the nearest thousandth

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Answer from: shimmerandshine1

0.384 = 38.4% probability that exactly two of their three children will have that trait.

Step-by-step explanation:

For each children, there are only two possible outcomes. Either they have the trait, or they do not. The probability of a child having the trait is independent of any other child. This means that the binomial probability distribution is used to solve this question.

Binomial probability distribution

The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.

$P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}$

In which $C_{n,x}$ is the number of different combinations of x objects from a set of n elements, given by the following formula.

$C_{n,x} = \frac{n!}{x!(n-x)!}$

And p is the probability of X happening.

Mr. and Mrs. Doran have a genetic history such that the probability that a child being born to them with a certain trait is 0.8.

This means that p = 0.8

Three children:

This means that n = 3

What is the probability that exactly two of their three children will have that trait?

This is P(X = 2).

$P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}$

$P(X = 2) = C_{3,2}.(0.8)^{2}.(0.2)^{1} = 0.384$

0.384 = 38.4% probability that exactly two of their three children will have that trait.

Answer from: Quest

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!

$4/2 = 2\\7/3.5=2\\8/4=2\\10/5=2$

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:

$y=\frac{x}{2}$

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.

Answer from: Quest

she gotta workk that a 2

step-by-step explanation: