Question

К осени цена на картофель понизилась сначала на 25%, а затем ещё раз понизилась на 70%, после чего картофель стал стоить 6,3 р. за килограмм. Найдите летнюю цену картофеля.

Answer 1

6,3р - (100-70=30%)
хр -100% ⇒х=6,3*100/30=21 р
21р - (100-25=75%)
хр -100% ⇒х=21*100:75=28 р - стоил картофель первоначально

Answer 2

100% - 25% = 75% стало стоить
100% - 70% = 30% стало стоить
0,75 * 0,30 = 0,225 = 22,5% всего произошло понижение
6,3 : 22,5/100 = 28 руб стоил картофель летом

Answer 3

Calculation of the Summer Price of Potatoes

To find the summer price of potatoes, we need to work backward from the given information. Let's break down the problem step by step:

1. The price of potatoes decreased by 25% initially. 2. Then, the price decreased by an additional 70%. 3. After these two price reductions, the potatoes were priced at 6.3 rubles per kilogram.

To find the original price of potatoes before the two reductions, we can use the following equation:

Final Price = Original Price - (Original Price x First Reduction) - (Original Price x Second Reduction)

Let's substitute the given values into the equation and solve for the original price:

6.3 = Original Price - (Original Price x 0.25) - (Original Price x 0.70)

Simplifying the equation:

6.3 = Original Price - 0.25 * Original Price - 0.70 * Original Price

Combining like terms:

6.3 = Original Price * (1 - 0.25 - 0.70)

Simplifying further:

6.3 = Original Price * 0.05

Dividing both sides by 0.05:

Original Price = 6.3 / 0.05

Calculating the original price:

Original Price = 126 rubles per kilogram

Therefore, the summer price of potatoes was 126 rubles per kilogram.