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# Three unbiased coins are tossed. What is the probability of getting at most two heads?

Option :

Explanation:

Solution:
Getting at most Two heads means 0 to 2 but not more than 2.
Here S = {TTT, TTH, THT, HTT, THH, HTH, HHT, HHH}
Let E = event of getting at most two heads.
Then E = {TTT, TTH, THT, HTT, THH, HTH, HHT}.
$\therefore P\left(E\right)=\frac{n\left(E\right)}{n\left(S\right)}=\frac{7}{8}$