Step-by-step explanation:
1.
when 3 coins are flipped the following outcomes are possible
h = heads, t = tails
h h h
h h t
h t h
h t t
t h h
t h t
t t h
t t t
yes, there have to be 8 options, because we have 3 positions with 2 possible outcomes. that means
2×2×2 = 2³ = 8 possibilities.
2.
at least 2 tails means 2 or 3 t in the list item :
h t t
t h t
t t h
t t t
3.
so, 4 out of the 8 possible outcomes. the probability is then therefore
4/8 = 1/2 = 0.5
