What are the odds against getting all heads or all tails in three successive flips of a coin?

I say it is 3:1, is this right?

2 answers

I don't think so. Lets look at it.

There are 2^3=8 things that can happen when you flip three coins.
Two of those HHH,or TTT is heads or tails.

so in 8 tries, one expects 2 heads/tails.

So in 8 trials, six are not heats or tails.

6:2 is the odds, and geepers, you are exactly right. Go to the head of the class.
some of the worst math I've ever seen