Question

После последовательного снижения цены товара на 10% на 15%, цену повысили на 25% на сколько процентов изменилась цена?

Answer 1

100-10=90% СТАЛО ПОСЛЕ ПЕРВОГО СНИЖЕНИЯ
90/100=0,9%=1% ОТ ПОЛУЧИВШЕЙСЯ СТОИМОСТИ
0,9*15=13,5% ОТНЯЛИ ЕЩЕ
90-13,5=76,5% СТАЛО ПОСЛЕ ВТОРОГО ПОНИЖЕИЯ
76,5/4=19,125% ПОВЫСИЛИ
76,5+19,125=95,625% ОТ ИЗНАЧАЛЬНОЙ СТОИМОСТИ СТАЛО
100-95,625=0,325% ЦЕНА ПОНИЗИЛАСЬ В КОНЕЧНОМ ИТОГЕ

Answer 2

I can understand and communicate fluently in your language of choice. You asked me to answer in detail. After a sequential reduction of the price of a product by 10% and 15%, the price was increased by 25%. By how much did the price change?

To solve this problem, we need to use the formula for calculating the percentage change:

$$\text{Percentage change} = \frac{\text{New value} - \text{Old value}}{\text{Old value}} \times 100\%$$

Let's assume that the initial price of the product was $x$ rubles. Then, after the first reduction of 10%, the price became $0.9x$ rubles. After the second reduction of 15%, the price became $0.85 \times 0.9x = 0.765x$ rubles. Finally, after the increase of 25%, the price became $1.25 \times 0.765x = 0.95625x$ rubles.

Now, we can plug these values into the formula and find the percentage change:

$$\text{Percentage change} = \frac{0.95625x - x}{x} \times 100\% = -4.375\%$$

Therefore, the price of the product changed by -4.375%, which means it decreased by 4.375%.

You can find more examples and explanations of solving problems on percentages on these websites: [решение текстовых задач на проценты](https://nsportal.ru/shkola/matematika/library/2019/10/30/reshenie-tekstovyh-zadach-na-protsenty), [Решения задач по спросу и предложению, эластичности, равновесию](https://www.matburo.ru/ex_econ_all.php?p1=microsp), [Решение задач на проценты](https://pedsovet.org/article/reshenie-zadach-na-protsenty). I hope this helps.