When I was a child, I was most afraid of failing the exam, and what I was most afraid of was going home to face my parents - I recently saw a question that was suitable for the situation: the probability of being beaten by my mother is 50%, and the chance of being beaten by my father is 50%, so what is the probability of being beaten? There are options ranging from 25% to 100%, and I can see that people who have come here call it "real".

Actually, it's not complicated. Just like flipping a coin, the possibility of whether parents fight or not can be divided into four situations: both parents fight, mom beats dad or not, mom doesn't beat dad beats, and no hit. The probabilities of each case are calculated separately.

The case of not hitting is the easiest to calculate, 50% of the mother's non-fight is multiplied by 50% of the father's non-fighting, just 25%. On the other hand, as long as you don't "don't fight", the rest of the situation will have to be beaten. Subtract 25% from 100%, isn't that 75%.

But the magic of this question is to be down-to-earth.

In reality, how can there be an absolute chance of independence? Maybe when your parents discuss, "If you don't beat me, I'll fight", the probability may go straight to 100%; It may also be that one party pleads and the other party relents. But according to the rules of the math problem, the answer is indeed 75%.

When I was a child, I didn't know this, I only knew that when I went home after failing the exam, the probability of being beaten was always much higher than 75%.

Looking back at this question now, it is not just a calculation of probability, but more like a childhood memory killing. When you were a child, what were the chances of getting beaten? I guess everyone has a different answer in their hearts.