The question is: the sales volume of mineral water a is four times that of mineral water B, and 275 bottles of mineral water a and B were sold. How many bottles of mineral water did you buy? I know the answer. A, 220 bottles; B, 55 bottles. But I won't tell her

Ah, my dear child, you can see that a mineral water is four times as much as B mineral water. Four B mineral water is one a mineral water. One a mineral water is four B mineral water. Add up a + B = B + B + B + B + B 12345. Look, they have five B mineral water. The title says that they sold 275 in total, so B + B + B + B = 275, that is, 5b = 275. B = 275 / 5

What are the aspects of good children's math problem essence

Chinese childhood thought that children's mathematics problems are more important than more. The essence can be expressed in three aspects: one is broad, the other is deep, and the third is understanding. It's reasonable to do more exercises. Don't we often say that "quantitative change causes qualitative change"? Learning knowledge points needs a process, especially digesting and absorbing ready-made knowledge into one's own ability

A 500 yuan leather coat is sold for 425 yuan after discount. It's a discount It's a discount. It's cheaper than the original price %．

(1) 425 △ 500 = 85% = 25% discount, (2) (500-425) △ 500, = 75 △ 500, = 15%, or 1-85% = 15%, so the answer is: 85%, 15

The current price of a computer is 2800 yuan, which is 700 yuan lower than the original price. How much lower?

700 ／ (2800 + 700) = 700 ／ 3500 = 0.2 = 20%; a: reduced by 20%

The original price of sharp 29 inch TV is 2500 yuan, which is 700 yuan more expensive than the current price. How much is the price reduction?
OK, I'll give you more!

700/2500=0.28=28%

The current price of a computer is 2800 yuan, which is 700 yuan lower than the original price. How much lower?

700 ／ (2800 + 700) = 700 ／ 3500 = 0.2 = 20%; a: reduced by 20%

Shopping malls are engaged in promotional activities. The original price of a certain brand of suit is 1600 yuan, and now it's sold at a 15% discount. How much money has it saved to buy such a suit now?

Saved 240 yuan~

There is a product, the original price is 3000 yuan, because the mall promotion, discount 5%, and then increase the price 5%, how much is the final product

Original price = 3000 yuan
Price after discount = original price * (1-5%) = 3000 * 0.95 = 2850 yuan
Price after price increase = price after discount * (1 + 5%) = 2850 * 1.05 = 2992.5 yuan
The result was 2992.5 yuan

Now it costs 1900 yuan to buy a color TV set. 600 yuan less than before. How much lower is the price of the color TV set?

A: the price of color TV sets has been reduced by 24%

Now it costs 1900 yuan to buy a color TV set. 600 yuan less than before. How much lower is the price of the color TV set?

A: the price of color TV sets has been reduced by 24%

The question is: the sales volume of mineral water a is four times that of mineral water B, and 275 bottles of mineral water a and B were sold. How many bottles of mineral water did you buy? I know the answer. A, 220 bottles; B, 55 bottles. But I won't tell her