It could go either way... There is a chance of getting more heads than tails or more tails than heads. But if you flip it an even amount of times the best estimation would be that about 50% of the time it will be heads and 50% of the time it will be tails... So you could estimate ABOUT 75 times!
You cannot have any expectations, statistics cannot apply here, you are as likely, in theory to get 150 heads as none at all as each coin toss is totally independent of the one before and after. Chaos theory would probably show that you are unlikely to get more or less than a certain number of heads or tails but mathematically there is absolutely no way of predicting a percentage out of any number of tosses.
