1.  Three unbiased coins are tossed. What is the probability of getting at most two heads?
A. 3/4
B. 1/4
C. 3/8
D. 7/8

Answer: Option D

Explanation:

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}.

P(E) = n(E) = 7 .
n(S) 8