There are 20 questions in the exam that determine the answer, but why does he want it?

In the exam, Xiaohua decided the answer by rolling the dice. There are 20 questions, but why did he throw them 40 times? Answer: He wants to check it again.

Because each judgment has two possibilities (20×2=40), it was thrown 40 times. Probability is a very important mathematical concept, which is used to describe the possibility of an event.

In life, we often encounter various events, such as dice, lottery, gambling and so on. The outcome of these events is often uncertain. Probability can help us calculate the possibility of these events and make more informed decisions.

The definition of probability is a number from 0 to 1, which indicates the probability of an event. 0 means that this event cannot happen, and 1 means that this event will happen. For example, when you roll a dice, the probability of each number appearing is 1/6, because the dice has six faces, and the probability of each face appearing is equal.

Probability can be calculated by the following formula: probability = number of favorable results/total results. For example, if you roll the dice, the probability of throwing 1 is 1/6, because only the face of 1 is 1, and there are six faces in total. Similarly, the probability of throwing an even number is 3/6, because there are 3 even faces, and there are 6 faces in total.

Probability has a wide range of applications in life:

For example, in insurance, finance, medicine, engineering and other fields. In the field of insurance, probability can be used to calculate the possibility of a certain risk, so as to determine the insurance cost.

In the financial field, probability can be used to calculate the fluctuation of stock price, so as to make investment decisions. In the medical field, probability can be used to calculate the prevalence of a certain disease, so as to formulate preventive measures. In the engineering field, probability can be used to evaluate the reliability of a certain equipment, so as to determine the maintenance plan.