The situation that demonstrates the law of large numbers is if you flip a coin 40 times and get tails about 20 times.
The situation that demonstrates the law of large numbers is: "If you flip a coin 40 times, you get tails about 20 times." This example illustrates that as the number of trials increases, the experimental (or empirical) relative frequency of obtaining tails approaches the theoretical probability, which is 0.5 for a fair coin.
The law of large numbers explains why, with a large number of flips, the relative frequency of obtaining tails should be close to 50%, even if in smaller samples, such as flipping the coin twice, you should not expect exactly one head and one tail.