What are the odds in favor of getting at least one head in three successive flips of a coin?
1 answer

"getting at least one head in 3 flips"
implies you don't want all 3 tails,
Pr(all 3 tails) = 1/8
Pr(at least one head) = 1  1/8 = 7/8
so odds in favour of at least one head
= 7:1