1。 Let's buy be- sell be+.

Then-8+9-10+11= 2 yuan. You still have 2 yuan in your wallet.

2。 You should have earned 1 1-8=3 yuan. But you earned 1 yuan (additional cost, 9- 10) by the middleman, so you got this 2 yuan. That is,11-8+9-10 = 2 yuan.

3。 The first transaction earned 1 yuan, so+1, the second transaction is the key. If you think it is really 1 yuan, then-1. At this time, the cost of chicken has been considered as 9 yuan by you ("9 yuan chicken, 10 yuan bought, 1 yuan lost"). When you think like this, you have actually acquiesced that "chicken should be 9 yuan chicken instead of 10 yuan chicken". Finally, when you sell it at 1 1 yuan, it must be 65438. This is why 10 cannot be subtracted by 1 1. That is, 9-8+9-10+11-9 = 2 yuan.

Although the thinking is different, each solution evolves from-8+9-10+11.

enclose herewith

PS: wrong view 1: 1 yuan profit

"8 yuan buys, 9 yuan sells" = 1.

"9 yuan sells, 10 yuan buys" =- 1.

"10 yuan buys, 1 1 yuan sells" = 1.

PS: Myth 2: 0 yuan Profit

I bought it for 8 yuan, sold it for 9 yuan, and earned it.

I bought it at 10 again, hanging upside down.

1 1 Sell again and make a profit.

I didn't post it backwards and I didn't earn it!

PS: Myth 3: 3 yuan Profit

I bought it for 8 yuan, sold it for 9 yuan, and earned it.

I bought it at 10 again. Put it back. At this time, I will break even.

1 1 sold it again, not 8, but earned 3?

PS: Myth 4: 6 yuan Profit

The purchase price of chicken in 8 yuan can be up to 1 1 yuan.

That is to say, this person should be able to reach 3 yuan at the highest level in a transaction.

So the first transaction lost 2 yuan's profits.

On the second transaction, he bought the commodity at the price of 10 yuan.

Obviously, 2 yuan's money was also lost in the purchase stage.

So this person should have made a profit in 6 yuan through two transactions.

PS: Several viewpoints reinvest the 1 yuan just earned from my pocket as a loss 1 yuan, but don't forget that I still have chickens. I sold 1 1 yuan, which means that I not only recovered my investment 1 yuan, but also earned/kloc-0. Even if the investment of 1 yuan is said to be a loss 1 yuan, you should come back when you recover the cost, so+1 (the first transaction)-1 (additional investment)+1 (cost recovery)+1 (.

General comment: The reason for the miscalculation lies in the violation of the most basic criterion in accounting-"Borrow and borrow". In layman's terms, buying and selling is trading! Business must be commensurate.

"9 yuan sells, 10 yuan buys"! It is not a transaction, otherwise "8 yuan Buying" and "1 1 Yuan Selling" are not up and down, and there is no causal relationship, so they cannot correspond. Therefore, there are two transactions in the question. You can't just take it apart. Namely:

"8 yuan buys, 9 yuan sells" = 1.

"10 yuan buys, 1 1 yuan sells" = 1.

So the question is simple. Don't complicate simple problems.

PS: Although this question is simple, it illustrates the most common phenomenon in daily economic life. Frequent trading behavior will increase transaction costs. Of course, transaction costs will always exist, and how to minimize this phenomenon is something that investors and managers consider. Ha ha! Besides, I feel wronged for the people in question. If you knew that 1 1 yuan could be sold, would you still sell it to a middleman? This is caused by "information asymmetry" and there is a way.