Question

The cost of $\text{5 litres}$ of milk is $₹116$. How much will $\text{7 litres}$ of milk cost?

Answer 1

Step:Finding the cost of milk.

Let the cost of $\text{7 litres}$ of milk be $₹x$

Therefore, The ratio of the quantity of milk is equal to the ratio of the cost of milk.

$$\begin{gathered} \text{⇒}\frac{5}{7}=\frac{116}{\mathrm{x}} \\ \Rightarrow \mathrm{x}\times 5=7\times 116 \\ \Rightarrow 5\mathrm{x}=812 \\ \Rightarrow \mathrm{x}=\frac{812}{5} \\ \Rightarrow \mathrm{x}=162.4 \end{gathered}$$

Hence, the cost of $\text{7 litres}$ of milk is $₹162.4$