Rahim tosses two coins simultaneously. The sample space of the experiment is {HH, HT, TH, TT}.
Total number of outcomes = 4
Outcomes in favour of getting at least one tail on tossing the two coins =
{HT, TH, TT}outcomes in favour of getting at least one tail = 3∴ Probability of getting at least one tail on tossing the two coins `="Number of outcomes in favour"/"Total number of outcomes"=3/4`