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

Can someone help me figure out how to solve this, please?

YOu could get

Htt
tHt
ttH
HHt
HtH
tHH
HHH

7 ways to get at least one head, and the probability of getting each one of those is 1/2*1/2*1/2 or 1/8

Pr= 7/8 getting at least one head.