When 3 unbaised coins are tossed, the total number of events = 8
They are {HHH, HHT, HTH, THH, TTH, THT, HTT, TTT}
(1) Number of favourable events (getting at least two heads) = 4
Probability of getting at least two heads = 4/8 = 1/2
(2) At most two heads
That is no head or one head or 2 heads
Probability of getting at most two heads = 7/8
The probability of getting exactly 2 heads is 12
The probability of getting atleast one head is 58
The probability of getting almost 2 tail is 38
The probability of getting exactly one tail is 38