Question

three unbiased coins are tossed.What is the probability of getting exactly two heads.​

Answer 1

When 3 unbiased coins are tossed, the sample space is {HHH, HTH, HHT, THH, THT, TTH, HTT, TTT] = 8

 

Event of getting two heads = {HTH, HHT, THH} = 3

 

P(Two Heads) = 3/8

 

Event of getting At least two heads (two or more than 2 heads) = {HHH, HTH, HHT, THH} = 4

 

P(At least Two Heads) = 4/8 = 1/2

 

Event of getting No heads = {TTT} = 1

 

P(No Heads) = 1/8