The price of a commodity is increased by 1 / 4, and then decreased by 1 / 4. Compared with the original big price, is the current price increased or decreased? How much is the increase (or decrease)? Speed! Don't use equation, just use formula directly!

(1) The current price is the original price; (1 + 1 / 4) × 3 / 4 = 15 / 16 = 93.75%
93.75%＜100%
A: the current price is lower than the original price
(2) Reduced; 100% - 93.75% = 6.75%
A: reduced by 6.75%

The original price of a computer is x yuan. How much is the price after 15% reduction

Price: X (1-15%) = 85% X Yuan

The original price of a computer is 5800 yuan, 800 yuan more expensive than the current price. How much is the original price more expensive than the current price

The current price is 5800-800 = 5000
5800/5000-1=0.16
It's 16% more expensive···

The current price of the computer is 2 / 11 lower than the original price, which is just 1000 yuan lower. How much is the current price

Original price: 5500

A shopping mall bought a batch of clothes at a certain price and sold them at a certain price. On average, it sold 10 pieces a day and made a total profit of 15000 yuan in 30 days. Now, in order to get back the money as soon as possible, the shopping mall decided to reduce the price of each piece of clothes by 20%. As a result, it sold 10 pieces more every day than before the price reduction, so that it could make a profit of 12000 yuan in 30 days?

Suppose the purchase price x selling price y 10 * 30 * (Y-X) = 15000 (10 + 10) * 30 * (0.8y-x) = 12000, then x = 100 and y = 150

The boss of a shopping mall bought a batch of clothes at the price of a yuan per piece. If B yuan per piece is sold, 15 pieces can be sold every day on average, with a total profit of 22500 yuan in 30 days. In order to recover the funds as soon as possible, the boss decided to reduce the price of each piece by 20%. As a result, 10 pieces more can be sold every day than before. In this way, the 30 day profit will still be 22500 yuan. How much is a 'and B?
To process, use binary linear equations, thank you!

(b-a)*15*30=22500
[(1-20%)b-a]*(15+10)*30=22500
B-A = 50
4b-5a=150
a=50
b=100

A shopping mall bought a kind of clothing at the price of 42 yuan per piece. According to the trial sale, the daily sales volume t (pieces) of this kind of clothing and the sales price x (yuan / piece) of each piece can be regarded as a functional relationship: T = - 3x + 204 (1) write the functional relationship between the daily sales profit y (yuan) of this kind of clothing and the sales price x (yuan) of each piece (2) through the formula of the obtained function, it is pointed out that if the market wants to get the maximum sales profit every day, what is the most appropriate sales price for each piece; what is the maximum sales profit?

(1) The functional relationship between the selling profit y (yuan) and the selling price x (yuan) is y = (X-42) (- 3x + 204), that is, y = - 3x2 + 330x-8568

A shopping mall bought a batch of clothes at the price of 40 yuan. If they were sold at 50 yuan per piece, 100 pieces could be sold in a week. When the price was increased by 1 yuan, the price of clothes would be increased by 1 yuan,
If the selling price of each piece is X Yuan and the total profit is y yuan, then the analytic function of Y with respect to X is____

y=｛100-5（x－50）｝▪（x－40）
{100-5 (x-50)} is the total sales volume, and (x-40) is the profit of each piece. The total profit = total sales volume × profit of each piece

If the purchase price is 80 yuan and you sell it at a 70% discount, can you still make a profit of 5% on the selling price?
The purchase price is 80 yuan. After a 70% discount, you can still make a profit of 5%. What is the original price?
The point m is on the line ab. in the following formulas, it can not be judged that M is the midpoint of the line ab
A.AB=2BM
B. BM = half ab
C.AM=BM
D.AM+BM=AB

1. Suppose the original price is x, 0.7x = 80 (1 + 5%) x = 120 yuan, the original price is 120 yuan
2. It can not be judged that M is the midpoint of line AB, and D is the midpoint of line ab

If you sell a piece of clothing at a 70% discount, you'll get a profit of 6 yuan. The price of this dress is 20 yuan. What's the purchase price?

Selling price: 20 * 0.7 = 14 yuan
Purchase price: 14-6 = 8 yuan

The price of a commodity is increased by 1 / 4, and then decreased by 1 / 4. Compared with the original big price, is the current price increased or decreased? How much is the increase (or decrease)? Speed! Don't use equation, just use formula directly!