Answer :
Answer:
Step-by-step explanation:To find the price of 1 liter of milk, we start by determining the price per deciliter (dl).
Given:
- 5 dl + 7 dl = 12 dl of milk costs 15.21 DL.
First, calculate the cost per deciliter:
\[ \text{Cost per deciliter} = \frac{15.21 \text{ DL}}{12 \text{ dl}} \]
\[ \text{Cost per deciliter} = 1.2675 \text{ DL} \]
Next, convert the cost per deciliter to cost per liter:
Since there are 10 deciliters in 1 liter:
\[ \text{Cost per liter} = 1.2675 \text{ DL} \times 10 \]
\[ \text{Cost per liter} = 12.675 \text{ DL} \]
Therefore, the price of 1 liter of milk is \( \boxed{12.675} \) DL.