Question

Купили 4 кг печенья по 8 рублей 20 копеек за килограмм и 3 кг конфет. За всю покупку заплатили 71 рубль 40 копеек. Сколько стоит 1 кг конфет?

Answer 1

1) 8.20 * 4=32.80(руб) заплатили за печенье

2) 71.40 - 32.80 = 38. 60 (руб) заплатили за печенье

3) 38. 60 : 3 = 12.8(руб) кг конфет

Ответ. кг конфет стоит 12.8 руб

Answer 2

Calculation of the Cost of Candy

To calculate the cost of 1 kg of candy, we need to determine the total cost of the candy and divide it by the total weight of the candy.

Given: - 4 kg of cookies at a rate of 8 rubles and 20 kopeks per kilogram - 3 kg of candy

Let's calculate the total cost of the cookies and the total cost of the purchase.

The total cost of the cookies can be calculated as follows: 4 kg * (8 rubles + 20 kopeks) = 32 rubles + 80 kopeks.

Now, let's calculate the total cost of the purchase: Total cost of the purchase = Total cost of the cookies + Total cost of the candy = 32 rubles + 80 kopeks + Cost of the candy.

We know that the total cost of the purchase is 71 rubles and 40 kopeks.

Therefore, we can write the equation: 32 rubles + 80 kopeks + Cost of the candy = 71 rubles + 40 kopeks.

To find the cost of the candy, we can subtract the total cost of the cookies from the total cost of the purchase: Cost of the candy = Total cost of the purchase - Total cost of the cookies.

Let's calculate the cost of the candy: Cost of the candy = 71 rubles + 40 kopeks - 32 rubles - 80 kopeks.

To simplify the calculation, let's convert the kopeks to rubles: 1 ruble = 100 kopeks.

Therefore, 80 kopeks = 80/100 = 0.8 rubles.

Now, let's substitute the values into the equation: Cost of the candy = 71 rubles + 40 kopeks - 32 rubles - 0.8 rubles.

Simplifying the equation: Cost of the candy = 38 rubles + 40 kopeks - 0.8 rubles.

Converting the kopeks to rubles: 40 kopeks = 40/100 = 0.4 rubles.

Substituting the values into the equation: Cost of the candy = 38 rubles + 0.4 rubles - 0.8 rubles.

Simplifying the equation: Cost of the candy = 37.6 rubles.

Therefore, the cost of 1 kg of candy is 37.6 rubles.