Question

Купили 1,2 кг конфет и 0,8 кг печенья. За всю покупку заплатили 35,96 р. Известно, что 1 кг конфет дороже 1 кг печенья на 1,8 р. Сколько стоит 1 кг конфет?

Answer 1

пусть х - кило конфет, 
а у - кило печенья тогда 

1,2х + 0,8у = 35,96 
х = у + 1,8 

используем метод подстановки 
1,2(у+1,8) + 0,8у = 35,96 
раскроем скобки 
1,2у + 2,16 +0,8у = 35,96 
перенесем неизвестные в одну сторону, а значения - в другую, меняя знаки 
2у = 35,96-2,16 
2у = 33,8 
у = 33,8/2 =16,9 

кило печенья стоит 16,90. 
раз конфеты на 1.8 дороже значит 
х = 16,90+1,8 = 18,70 

Ответ: 18.70 р.

Answer 2

0.8х+1.2(х+1.8)=35.96

0.8х+1.2х+2.16=35.96

2х=35.96-2.16

2х=33.8

х=33.8:2

х=16.9руб-стоит 1кг печенья.

16.9+1.8=18.7руб-стоит 1кг конфет.

Answer 3

Problem Analysis

We are given the following information: - 1.2 kg of candies and 0.8 kg of cookies were purchased. - The total cost of the purchase was 35.96 rubles. - The price of 1 kg of candies is 1.8 rubles more than the price of 1 kg of cookies.

We need to determine the cost of 1 kg of candies.

Solution

Let's assume the cost of 1 kg of cookies is x rubles. According to the given information, the cost of 1 kg of candies is x + 1.8 rubles.

We can set up the following equation based on the total cost of the purchase:

1.2 * (x + 1.8) + 0.8 * x = 35.96

Simplifying the equation:

1.2x + 2.16 + 0.8x = 35.96

Combining like terms:

2x + 2.16 = 35.96

Subtracting 2.16 from both sides:

2x = 33.8

Dividing both sides by 2:

x = 16.9

Therefore, the cost of 1 kg of cookies is 16.9 rubles.

To find the cost of 1 kg of candies, we can substitute the value of x into the equation:

1 kg of candies = 16.9 + 1.8 = 18.7 rubles.

Answer

The cost of 1 kg of candies is 18.7 rubles.