Question

The cost of 5 kilogram of sugar is 72 rupees. Find out the cost of 15 kilogram of sugar.

Answer 1

Hint: Find the cost of 1 kg of sugar by dividing the cost of 5kg sugar by total quantity that is 5. Then, multiply the cost of 1 kg of sugar to 15 to find the cost of 15 kg of sugar. Thus, we find the required answer using a unitary method.

Complete step-by-step answer:
We are given that the cost of 5 kilogram of sugar is 72 rupees.
We will first find the cost of 1 kilogram of sugar.
To find the cost of one kilogram of sugar, divide 72 by 5.
Hence, the cost of 1 kg sugar is ${\text{Rs}}{\text{. }}\dfrac{{72}}{5}$.
Now, we have to find the cost of 15 kilogram of sugar.
Multiply the cost of 1 kg of sugar to the total quantity of sugar.
Therefore, the cost of 15 kg of sugar is calculated as,
${\text{Rs}}{\text{. }}\dfrac{{72}}{5} \times 15$
On solving the above expression, we will get,
${\text{Rs}}{\text{. }}\dfrac{{72}}{{{5}}} \times {{15}}3 = 72 \times 3 = {\text{Rs}}{\text{.216}}$
Hence, the cost of 15 kg of sugar when the cost of 5 kilogram of sugar is 72 rupees is 216 rupees.

Note: The method where we find the value of a single item by dividing the value of all given items by the number of given items and then multiplying the value of a single item to the required number of items is known as the unitary method. In this question, we have used the unitary method to get the required answer.