Two coins are tossed simultaneously. What is the probability of getting at least one tail?

$\dfrac { 3 } { 4 }$

Step by Step Explanation:
1. When two coins are tossed simultaneously, all possible outcomes are $HH, HT, TH, TT$.

The total number of all possible outcomes = $4$.

2. Let $E$ be the event of getting at least one tail.

Therefore, $E$ is the event of getting $1$ tail or $2$ tails.

So, the favourable outcomes from $HH, HT, TH, TT$ are $HT, TH$ and $TT$.

Number of favourable outcomes = 3. \begin{aligned} \therefore \space P(\text{getting at least one tail}) = P(E) = \dfrac { 3 } { 4 }. \end{aligned}
3. Therefore, the probabilty of getting at least one tail is $\dfrac { 3 } { 4 }$.