# If a coin is tossed twice, find the probability of getting at least one head. a) 3​/4 b) 2​/3 c) 1​/2 d) 1​/4

Option a) 3/4.

When two coins are tossed:
S=HH,HT,TH,TT
The probability of this is approximately 1/2, so the probability of two in a row is 1/2∗1/2=1/4
The probability of getting at least one head is 1−1/4=3/4