Is there anything that has a probability of about 1 5 ?

The probability of something happening is probably, not exactly. If you say that it is accurate, then I can only give you a calculation problem from elementary school, for example, if I buy a thousand oranges and find that 15 of them are bad, what is the probability of buying bad oranges. And probably, in fact, it means that the probability of things happening is very low, and the probability is very small.

But things that require an exact probability to be close are not necessarily thought of all at once. If you say that you buy a lottery ticket and win the lottery and step on dog shit on the road, this probability should be lower than that; But if you talk about the probability of meeting a girl on the street, the probability of flipping a coin face up, it must be very large, even 100% encountered. Therefore, if we want to directly transform the possibility of an abstract thing into a concrete probability, it is actually difficult to do it, so we might as well start from the probability side and rely on the concrete number to the abstract thing.

For example, if you buy 100 apples, is it possible to close the probability of buying bad apples? You go to buy sports lottery tickets, buy the odds of winning and losing, especially the teams with very different forces, the probability is not close; Walking on the street, the proportion of people under the age of 5 can be approached.

Therefore, when it is more difficult to think from the abstract to the concrete, you might as well change the perspective, starting from the concrete, the base number is set at one hundred, and the probability of something appearing can be. Or it's easier to think of something in life if you think of it as digital.

But it's actually a very boring question, and I've been discussing it seriously for so long, I don't know what the intention of the person asking the question is. Is it a very special number, or maybe you're just asking this question because the 5 and % positions on the keyboard are the same key. But in the end, I still have your question, and I hope you can get something out of it, whether it's an answer, a good thing, or a good thing to find yourself bored.

There is a possibility of anything, and this probability must also exist, but it may not have been studied yet, and it is really not possible to say it now.

The probability of many things is very small, and it is difficult to say that the probability of things happening is this number, but we must know that many things in society are small probability events.

Probably, it means that it is unlikely to happen, and there are many around you, such as an honor student who turns in a blank paper during the college entrance examination, and that may be a sudden event that causes the paper to be invalid.

Prepare an opaque bag containing 200 small balls of equal size, 3 of which are white and the others are black, you randomly sample, and the probability of touching the white balls is.

Yes Whatever the odds are, it's just very unlikely that they will happen.

Yes, there are many wonders in the world. What it is, this remains to be verified. But there must be one. There is only something in this world that people can't think of, and nothing that won't happen.

Of course, this kind of thing exists, for example, it is very common in normal times, but you don't calculate the probability of it. This is similar to something that has a very small probability.

According to the analysis of probability theory and mathematical statistics, the probability of many things can be calculated, but most of the time we don't take the time to calculate because it may not be meaningful.

There must be, but it's not very common, it's generally whole, and there's no point in discussing such probabilities because we're not mathematicians.

Yes, a lot of things. It can be remembered as a relatively small occurrence event. The landlord can test it with cards.

Summary. The probability of an event is that the probability of occurring 11 times in a row is: to the 11th power.

What is the probability of an event happening 11 times in a row?

The probability of an event is that the probability of occurring 11 times in a row is: to the 11th power.

Because every time the probability is the same, you need to multiply all of them.

The probability of this is very low.

Probability, also known as "probability", is a reflection of the probability of a random event occurring. Random events refer to events that may or may not appear in Songshan under the same conditions.

Playing mahjong and losing 11 times in a row, does it meet this probability?

Congruent.

Still, and always will be.

There is a principle in probability that a finite number of samples is negligible for the probability determined by an infinite number of samples. For example, if a coin is tossed 10 times in a row, it is an emblem, and when it is tossed for the 11th time, the probability of its word appearing is still, and the probability of the 11th time will not be affected by the result of the previous 10 times.

And never will.

1、（1－0. 08）ⁿ＝x

XPS: First of all, n 7, the phone can't hit the superscript 7.

And then maybe your description has a little bit of a problem, and I understand that it didn't happen once in 7 times.

The probability of a positive occurrence p=

Number of experiments n=1000

Thus, the two general conditions are satisfied.

p(x=900)=p 900*q 100=Here we get the probability p(x=500) of exactly 900 times out of 1000 trials

p^500*q^500=

Based on the above calculations, we find that no matter how many heads are thrown in 1000 rounds, the probability is the same.

Of course, the above is the probability of exactly n times, if you find less than 500 times out of 1000 times, obviously you should sum all the numbers, so it is exactly 1 2

If it is found less than 900 times out of 1000 times, it should also be summed from 0 to 900, and the result is that if it is more than 900 out of 1000 times, it should be summed with 900--1000, and the result is.

The probability of throwing a coin a thousand times and 900 heads is a combination of 1000 times multiplied by 1000 times in the probability of 1,000 coins and 100 times in tails (1 2).

Toss a coin a thousand times, the probability of heads 500 times, (1 2) to the power of 1000, multiplied by 1000 to take the combination of 500 times.

The combination of 100 times out of 1000 times is to take out 100 numbers out of a thousand numbers, and how many different ways to take them. I shouldn't have learned it in junior high school, so I want to think about it again, and I hope there is a prawn to teach me.

Set p(a)=,p(b)=

So there are: p(a)=,p(b)=

Again, by the question: p(ab )=

So p(aub)=p(a)+p(b)-p(ab)=so p((aub)b)=p(aub)+p(b)-p(aub)ub).

then the following: p((aub) b)=p((aub)b) p(b)=p(a)=,p(b)=

So there is: p(a)=

And from the question p(a b)= so p(ab)=p(a b)p(b)=p(a b)=p(a b)=, then p(a b)=p(a b)p(b)=so (1)p(aub)=p(a)+p(b)-p(ab)=(2)p(a ub)=p(a)+p(b)-p(a b)=