Question

A coin is tossed three times. What is the probability of getting at least one tail?

Answer 1

To find the probability of getting at least one tail in tossing a coin three time,

let the event is A

total outcomes=$8$

these are

$(TTT,TTH,THT,THH,HTT,HTH,HHT,HHH)$

Favourable outcome of getting at least one tail are $7$ these are :$TTT,TTH,THT,THH,HTT,HTH,HHT$

$\mathrm{Probability}=\frac{\mathrm{favourable}\mathrm{outcome}}{\mathrm{Total}\mathrm{outcome}}$

Now, Probability of getting at least one tail

$P\left(Atleastonetail\right)=\frac{7}{8}$

Hence, the probability of getting one tail is $\raisebox{1ex}{$7$}\!\left/ \!\raisebox{-1ex}{$8$}\right.$.