）The original price of Andersen's fairy tales is 24 yuan, and the current price is 4 yuan cheaper than the original price. How much is the current price lower than the original price? Formula

）The original price of Andersen's fairy tales is 24 yuan, and the current price is 4 yuan cheaper than the original price. How much is the current price lower than the original price? Formula

Take the original price as the unit 1, the current price is 1 minus 1 / 6, that is 5 / 6. If you multiply the original price by 5 / 6, you will get 20 yuan. This is the current price. 24-20 = 4 yuan. The current price is 4 yuan cheaper than the original price

The original price of Andersen's fairy tales was 24 yuan. The current price is 1 / 6 lower than yuanla. How much lower is the current price?

Now the price is reduced by 24 × 1 / 6 = 4 yuan

Xiao Li saved money to buy a set of four encyclopedia knowledge series, the total price was 23.2 yuan. Xiao Li saved enough money to buy books in the bookstore, but happened to meet the sales promotion of the bookstore. The encyclopedia knowledge series sold only 17.4 yuan, and Xiaoli used the remaining money to buy two notebooks

17.4 △ 4 = 4.35 (yuan)
（23.2-17.4）÷2
=5.8÷2
=2.9 yuan
A: the average price of a book is 4.35 yuan, and the price of a notebook is 2.9 yuan

Xiao Li and Xiao Hua went to the bookstore to buy books. They saw a set of two books on scientific exploration. When they looked at the price, Xiao Li: my money is still 8.5 yuan short; Xiao Hua: I don't have enough money, which is still 11.7 yuan. As a result, after a discussion, the combined money can buy a set of scientific exploration series. Do you know the price of a set of scientific exploration books?

8.5 + 11.7 = 20.2 yuan, because if the money for two people is just enough to buy scientific exploration, it must be twice the sum of the money they have and the money they should have. That is, the sum of money that Xiaoli had and Xiaohua had, or that of Xiaohua and Xiaoli was the price of the book

A bookstore sells a new book at a 10% discount from the list price, and can still make a profit of 20%. If the purchase price of the book is 21 yuan, the price is () A. 26 yuan B. 27 yuan C. 28 yuan D. 29 yuan

The price is x yuan, according to the meaning of the title: 0.9x = 21 (1 + 20%),
The solution is: x = 28,
Therefore, C

A bookstore sells a new book at a 10% discount from the list price, and can still make a profit of 20%. If the purchase price of the book is 21 yuan, the price is () A. 26 yuan B. 27 yuan C. 28 yuan D. 29 yuan

The price is x yuan, according to the meaning of the title: 0.9x = 21 (1 + 20%),
The solution is: x = 28,
Therefore, C

A bookstore sells a new book at a 10% discount from the list price, and can still make a profit of 20%. If the purchase price of the book is 21 yuan, the price is () A. 26 yuan B. 27 yuan C. 28 yuan D. 29 yuan

The price is x yuan, according to the meaning of the title: 0.9x = 21 (1 + 20%),
The solution is: x = 28,
Therefore, C

A bookstore sells a new book at a 10% discount from the list price, and can still make a profit of 20%. If the purchase price of the book is 21 yuan, the price is () A. 26 yuan B. 27 yuan C. 28 yuan D. 29 yuan

The price is x yuan, according to the meaning of the title: 0.9x = 21 (1 + 20%),
The solution is: x = 28,
Therefore, C

A bookstore sells a new book at a 10% discount from the list price and still makes a profit of 20%. If the book's purchase price is 21 yuan, how much is the price? I'm not stupid. It's just that I don't have a clue in my head to explain this question. It's not just the answer. The more detailed the better, it will be added if I understand it If you can 21*(1+20%)/90%

Did you learn equations?
If the price is x yuan, the selling price is 0.9x. We say that the profit of 20% generally refers to 20% of the purchase price, so the equation can be formulated
Selling price - purchase price = profit
9 x-21 = 21 × 0.2
The solution is x = 28

A bookstore sells a new book at a 10% discount from the list price and still makes a profit of 20%. If the book's purchase price is 21 yuan, how much is the price? It's a linear equation of one yuan Yes, it can be 5

90%x=21（1+20%）
90%x=25.2
x=28
Remember to add points