Question

A class is made up of 2 boys and 10 girls. Half of the girls wear glasses. A student is selected at random from the class. What is the probability that the student is a girl with glasses

Answer 1

Given that:

`\begin{gathered} \text{Number of boys =2} \\ \text{Number of girls =10} \\ \text{Total population =12} \end{gathered}`

Given that half of the girls wear glasses, this implies that

`\text{Number of girls with glasses = 5}`

The probability of an event is expressed as

`Pr(\text{event)}=\frac{\text{Number of desired outcome}}{Number\text{ of favourable outcome}}`

Thus, the probability that a student selected at random is a girl with glasses is evaluated as

`\begin{gathered} Pr(\text{girl with glasses})=\frac{\text{number of girls with glasses}}{total\text{ number of students}} \\ =(5)/(12) \end{gathered}`

Hence, the probability that the student selected at random is a girl with glasses is

`(5)/(12)`