Question

Two coins are tossed once. Find the probability of getting

1) 2 heads

2) at least 1 tail.

Answer 1

When two coins are tossed, the sample space, S = {(H, H), (H, T), (T, H), (T, T)}

Thus, the total number of outcomes = 4

1) Let A be the event of getting 2 heads.

Thus, outcome favouring A is {(H, H)}

`∴ P(A) = 1/4`

2) Let B be the event of getting at least 1 tail

At least 1 tail means 1 tail or 2 tails.

The outcomes favouring B is {(H, T), (T, H), (T, T)}

`∴ P(B) = 3/4`