Question

Cost of 5 kg rice is Rs. 107.50. What quantity of rice can be purchased for Rs. 64.5?

Answer 1

Hint: We have to find the quantity of rice which can be purchased for Rs. 64.5 by using the unitary method first, we will find the cost of 1 kg rice. Then, we will divide the cost of one kg rice with the cost at which we have to find the quantity of rice.

Complete step-by-step solution:
Given: Cost of 5 kg rice = Rs. 107.50
By using unitary method,
We will find the cost of 1 kg rice.
Cost of 1 kg rice = $\dfrac{{{\text{cost of 5 kg rice}}}}{5}$
Substituting the values in the above equation.
Cost of 1 kg rice $ = \dfrac{{107.5}}{5}$
Cost of 1 kg rice $ = Rs.21.5$
Now, we will find the quantity of rice which can be purchased for Rs. 64.5.
Quantity of rice $ = \dfrac{{64.5}}{{21.5}}$
Quantity of rice $ = 3kg$
So, 3 kg rice can be purchased for Rs. 64.5.

Note: The unit price of an item is the cost per unit of the item. We divide the price of a certain number of units of an item by the number of units to find the unit price of that item.
The unitary method is a technique for solving a problem by first finding the value of a single unit, and then finding the necessary value by multiplying the single unit value. In essence, this method is used to find the value of a unit from the value of a multiple, and hence the value of a multiple.