Question

В начале года в магазине "Сделай сам" винтики, шпунтики и гаечки продавались по одинаковой цене 100 рублей за 1 кг. 30 февраля цены на винтики повысились на 50%, а цены на шпунтики понизились на 50%. 31 февраля цены на винтики понизились на 50%, а цены на шпунтики повысились на 50%. Какой товар будет самым дорогим в марте? Ответ объясните.

Answer 1

1) 50% от 100 =50.  

2) 100+50=150(р.) стали винтики.

3) 100-50=50(р) стали шпунтики.

4) Теперь нам нужно найти 50% от 150. 150/100*50=75.

5) 150-75=75(р.) стали винтики.

6) 50% от 50= 50/100*50=25.

7) 50+25=75(р) стали шпунтики.

Итог: самыми дорогими остались гаечки т.к. их цена неизменилась и осталась 100р.

Answer 2

Problem Analysis

In this problem, we are given the prices of screws, bolts, and nuts in a store called "Сделай сам" (Do It Yourself) at the beginning of the year. On February 30th (which doesn't exist), the price of screws increased by 50%, while the price of bolts decreased by 50%. On February 31st (which also doesn't exist), the price of screws decreased by 50%, while the price of bolts increased by 50%. We need to determine which item will be the most expensive in March.

Solution

To solve this problem, let's analyze the changes in prices for screws, bolts, and nuts step by step.

1. Initial Prices: - Screws: 100 rubles per 1 kg. - Bolts: 100 rubles per 1 kg. - Nuts: 100 rubles per 1 kg.

2. February 30th: - Screws: Price increased by 50%. New price = 100 + (50% of 100) = 150 rubles per 1 kg. - Bolts: Price decreased by 50%. New price = 100 - (50% of 100) = 50 rubles per 1 kg. - Nuts: No change in price. Price remains 100 rubles per 1 kg.

3. February 31st: - Screws: Price decreased by 50%. New price = 150 - (50% of 150) = 75 rubles per 1 kg. - Bolts: Price increased by 50%. New price = 50 + (50% of 50) = 75 rubles per 1 kg. - Nuts: No change in price. Price remains 100 rubles per 1 kg.

Based on the above calculations, we can see that the prices of screws and bolts will be the same in March, both costing 75 rubles per 1 kg. Therefore, screws and bolts will be tied as the most expensive items in March.

Conclusion

In March, both screws and bolts will be the most expensive items in the "Сделай сам" store, with a price of 75 rubles per 1 kg. The price of nuts will remain unchanged at 100 rubles per 1 kg.