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Venn diagrams are a highly effective graphical approach for representing the sample space S and its subsets. According to net ratings, 4% of individuals frequent MySpace, 3% visit Bebo, and 1% visit MySpace and Bebo. Let A represent the event in which citizens visit MySpace and B represent the event in which citizens visit Bebo.

Therefore,

$\begin{array}{c}\mathbf{P}\mathbf{\left(}\mathbf{C}\mathbf{\right)}\mathbf{=}\mathbf{4}\mathbf{\%}\\ \mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{=}\frac{\mathbf{4}}{\mathbf{100}}\\ \mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{=}\mathbf{0}\mathbf{.}\mathbf{04}\end{array}$

$\begin{array}{c}\mathbf{P}\mathbf{\left(}\mathbf{B}\mathbf{\right)}\mathbf{=}\mathbf{3}\mathbf{\%}\\ \mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{=}\frac{\mathbf{3}}{\mathbf{100}}\\ \mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{=}\mathbf{0}\mathbf{.}\mathbf{03}\end{array}$

$\begin{array}{c}\mathbf{P}\mathbf{\left(}\mathbf{C}\mathbf{\right)}\mathbf{=}\mathbf{1}\mathbf{\%}\\ \mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{=}\frac{\mathbf{1}}{\mathbf{100}}\\ \mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{=}\mathbf{0}\mathbf{.}\mathbf{01}\end{array}$

The Venn diagram below represents the country's use of social networking sites:

The probability that a person will visit either MySpace or Bebo social networking sites is denoted by $\mathbf{P}\mathbf{(}\mathbf{A}\mathbf{鈭�}\mathbf{B}\mathbf{)}$, and it is determined using the additive rule of probability:

$$\begin{gathered} \mathbf{P}\mathbf{(}\mathbf{A}\mathbf{鈭�}\mathbf{B}\mathbf{)}\mathbf{=}\mathbf{P}\mathbf{\left(}\mathbf{A}\mathbf{\right)}\mathbf{+}\mathbf{P}\mathbf{\left(}\mathbf{B}\mathbf{\right)}\mathbf{鈭�}\mathbf{P}\mathbf{(}\mathbf{A}\mathbf{鈭�}\mathbf{B}\mathbf{)} \\ \mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{=}\mathbf{0}\mathbf{.}\mathbf{04}\mathbf{+}\mathbf{0}\mathbf{.}\mathbf{03}\mathbf{鈭�}\mathbf{0}\mathbf{.}\mathbf{01} \\ \mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{=}\mathbf{0}\mathbf{.}\mathbf{06} \end{gathered}$$

Hence, the required probability is 0.06.

The chance of a citizen not visiting either social networking site is represented by the probability of the occurrence $\mathbf{P}\mathbf{(}\mathbf{A}\mathbf{鈭�}\mathbf{B}\mathbf{)}$

$$\begin{gathered} \mathbf{P}{\left(A鈭�B\right)}^{\mathbf{C}}\mathbf{=}\mathbf{1}\mathbf{鈭�}\mathbf{P}\mathbf{(}\mathbf{A}\mathbf{鈭�}\mathbf{B}\mathbf{)} \\ \mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{=}\mathbf{1}\mathbf{-}\mathbf{0}\mathbf{.}\mathbf{06} \\ \mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{=}\mathbf{0}\mathbf{.}\mathbf{94} \end{gathered}$$

Hence, the required probability is 0.94.