Learn and know about the unitary method and its uses i.e. applications. If it is given that the cost price of 9 apples is Rs.45 then what is the cost price of 15 apples? Can you solve and find the answer. Directly we can’t say the cost price of 15 apples. For finding the answer i.e. cost price of 15 apples we should use the unitary method.
Now we will learn what is unitary method and how to apply it to solve the above given problem. Form the name itself we can understand something i.e. unitary meaning is unit i.e. 1 and method means a process. It says that first find cost price of 1 unit or things then you can find cost price of any number of units or things. So if you want to find the cost price of 15 apples first we should find the cost price of 1 apple. After finding cost price of 1 apple, then it is easy to find the cost price of 15 apples.
Cost price of 9 apples is 45
Cost price of 1 apple is 45/9 = 5
Therefore, cost price of 15 apples is 15 × 5 = 75.
Some unitary method sums and solutions:
♦ The selling price of 3 pens is 48 then find the selling price of 4 pens.
First, find out the selling price of one pen.
It is given that,
Selling price of 3 pens is Rs.48, then
Selling price of 1 pen is Rs.48/3 = Rs.16.
The selling price of 4 pens is Rs. 4 ×16 = Rs.64
♦ The weight of 12 books is 60kg then what is the 1 book weight?
1 book weight is 60/12 kg = 5 kg.
I hope from the above examples, it is very easy to understand what is unitary method.