Principle of drawing lots: Prove that two people draw lots the same, draw lots first and then draw lots.

The principle of drawing lots comes from the total probability formula, which means that the order of drawing lots has nothing to do with the probability of winning lots, and the probability of drawing first is the same as that of drawing later.

For example, there are five labels in the pocket, two of which are physical labels and the rest are blank labels. Two people are arguing about priorities, and C is invited to help. C said: in fact, it is the same who draws first and then draws. Do you think what C said makes sense?

Proof: Because even if the first person smokes a lot, the other person still has a chance to smoke a lot.

The probability of drawing something first is 2/5; Probability of drawing the object label after drawing: 1/4 if the object label is drawn first, and 1/2 if the blank label is drawn first.

So in the lottery, it is the same to draw first and then draw, regardless of the order of the lottery.