The probability of the event to occur is:
[tex]P(E)=\frac{\#\text{ of outcomes at which the event occurs}}{To\text{tal number of outcomes}}[/tex]
The number of outcomes at which the person is over 40 years of age and drink root beer is: 30
The total number of outcomes is: 40+35+20+25+20+30+20+30+25=255
The probability is then:
[tex]\begin{gathered} P(E)=\frac{30}{255} \\ \text{Simplify dividing by 15 the numerator and the denominator:} \\ P(E)=\frac{30/15}{255/15}=\frac{2}{17} \end{gathered}[/tex]
