Here's an example: if I were to tell you, let's play a little coin toss game, and I'm going to flip a coin, and if it comes up heads, I'm going to pay you 10 dollars, but you have to pay four dollars for the privilege of playing with me, most of you would say, sure, I'll take that bet. Because you know that the odds of you winning are one half, the gain if you do is 10 dollars,
ここに例があります 例えば　コイン投げゲームをして 表が出たら10ドルもらえます でもこのゲームに参加するには4ドル払わなければなりません ほとんどの方は この賭けにのるでしょう なぜならあなたが勝つ確率は2分の１で 買った場合のもうけは10ドルで