The probability of getting two tails when two coins are tossed is

Concept: Probability of getting probability of the occurrence of an event is$P\left(E\right)=\frac{\text{Total number of favorable outcomes}}{\text{Total number of outcomes}}$.

Here, the sample space when two coins are tossed $=\left\{\right(\text{H},\text{H}),(\text{H},\text{T}),(\text{T},\text{H}),(\text{T},\text{T}\left)\right\}$

That is, $n\left(S\right)=4$

The event $E$of getting two tails $(T,T)=1$

Now, $n\left(E\right)=1$

Thus, the probability of getting two tails, $P\left(E\right)=\frac{n\left(E\right)}{n\left(S\right)}=\frac{1}{4}$.

Hence, the probability of getting of getting two tails when two coins are tossed is $\frac{1}{4}$.