The experimental probability is given by
We can find the theoretical probability by
As we can see, the experimental probability is bigger than the theoretical probability, which means that the theoretical probability is wrong? No! If we continue to flip coins, over and over, like 1000 flips, we will see that the result will tend to the theoretical, the point is, how many flips should we do? We also don't know! It's impossible to calculate it right now, but we know it will converge to the theoretical probability.