Question

Suppose S and T are mutually exclusive events. Find P(S or T) if P(S) = 8/9 and P(T) = 1/10.

Answer 1

`\textbf{$P(S \cap T) = (89)/(90)$ }\\`

Explanation:

`\textup{Mutually events are events that cannot occur at the same time.}\\\textup{When you toss a coin you get only $head$ or only $tail$ but never both.}\\ \textup{In mathematical terms $P(A) \cup  P(B) = 0$, where $A$ and $B$ are mutually exclusive events. }\\\textup{We know the formula:}\\$$ P(A \cup B) = P(A) + P(B) - P(A \cup B) $$\\\textup{When $A$ and $B$ are mutually exclusive, it will simply be:}\\$$ P(A \cup B) = P(A) + P(B) $$\\\textup{Now given:}\\ $P(S) = 8/9$ , $P(T) = 1/10$\\`

`$ \implies P(S \cup T) = (89)/(10)$`