Problem 7. Among Vulcans, there is a trait known as Sehlat Fangus Magma; Vulcans
ID: 3203252 • Letter: P
Question
Problem 7. Among Vulcans, there is a trait known as Sehlat Fangus Magma; Vulcans with this trait enjoy petting large Sehlats. Note that Sehlats are like live Teddy Bears with fangs. Those who don't have Sehlat Fangus Magma prefer petting small Sehlats. As a research geneticist, you perform a study with a sample size of 53 subjects. The breakdown of individuals by phenotypes is as follows: 7 individuals are male and have Sehlat Fangus Magma; 22 individuals are female and have Sehlat Fangus Magma; 3 individuals are male and do not have Sehlat Fangus Magma; 21 individuals are female and do not have Sehlat Fangus Magma. Question A. What is the probability a Vulcan is female? Question B. What is the probability a Vulcan has Sehlat Fangus Magma and is female? Question C. What is the probability a Vulcan has Sehlat Fangus Magma given that she is female?
Explanation / Answer
A. P(Vulcan is female) = Number of female vulcans / Total number
= (22+21)/53 = 43/53 = 0.8113
B. P(Vulcan has Sehlat Fangus Magma and is female) = Number of individuals who are female and have Sehlat Fangus Magma / Total
= 22/53 = 0.4151
C. P(Has Sehlat Fangus Magma | Female) = P(Has Sehlat Fangus Magma and Female) / P(Female)
= (22/53) / (43/53) = 22/43 = 0.5116