Question

Giving a test to a group of students, the grades and gender are summarized below ABCTotalMale321419Female542029Total863448If one student is chosen at random,Find the probability that the student was male OR got a/an "C". Round to at least 3 decimal places.

Answer 1

0.813

Explanations:

Probability is the likelihood or chance that an event will occur. The probability that the student was male OR got a/an "C" is as shown:

P(male or a C) = Pr(male) + Pr(C) - Pr(male and C)

Pr(male U C) = Pr(male) + Pr(C) - Pr(male n C)

Given the following probabilities

`\begin{gathered} Pr(male)=(19)/(48) \\ Pr(C)=(34)/(48) \\ Pr(male\text{ U C})=(14)/(48) \end{gathered}`

Substitute the probability to have:

`\begin{gathered} Pr(male\text{ }U\text{ C})=(19)/(48)+(34)/(48)-(14)/(48) \\ Pr(male\text{ }U\text{ C})=(19+34-14)/(48) \\ Pr(male\text{ }U\text{ C})=(39)/(48) \\ Pr(male\text{ }U\text{ C})=(13)/(16) \\ Pr(male\text{ }U\text{ C})=0.813 \end{gathered}`

Hence the probability that the student was male OR got a/an "C" is 0.813