2nd Class Mathematics Addition Addition

Addition

 

Addition is the method by which we can add two or more quantities. Therefore; in an addition two or more numbers are involved. Before knowing the rules of the addition, look at the following.

Let us add: 5 + 9

Therefore, 5 + 9 = 14

 

•      Example:

            How many erasers are there in all, if a boy has 6 erasers and his sister has 8 erasers?

            (a) 14 erasers                                                      (b) 19 erasers

            (c) 21 erasers                                                      (d) All the above

            (e) None of these

Ans.     (a)

            Explanation: Total number of erasers = 6 + 8 = 14. Therefore, option (a) is correct,

 

•      Example:

There are 4 mango tree in each row in a mango garden. How many mango trees are there in all, if 4 rows are there in a garden?

            (a) 18                                                                (b) 16

            (c) 15                                                                (d) All the above

            (e) None of these

Ans.     (b)

            Explanation: Total number of mango trees = 4 + 4 + 4 + 4 = 16. Therefore, option (b) is correct.

 

Rules for Addition

            The following are the rules for the addition of more than one digit numbers.

 

Rule: 1

            Start addition with the 1st digit from right, then with 2nd digit from the right and the process goes on.

            In another words, add ones 1st: then tens: then hundreds and so on.

            Look at the following addition:

            14 + 15 =?

           

Rule: 2

If addition of ones gives result in 2 digits, then add the left digit of the result with tens and the process goes on.

            Look at the following addition:

            25 + 26 =?

           

           

            Here, the left 1 of 11 is added to 4 as below:

           

             

•      Example:

            The following are the stock of the given articles in a general store

Name of articles	Quantity (Pieces)
Soap	33
Tooth brush	11
Chocolates	13

 

How many articles are there in all?

            (a) 23                                                                (b) 44

            (c) 57                                                                (d) All the above

Ans.     (c)

            Explanation: Therefore, option (c) is correct,

 

•      Example:

            Add 56 and 97.

            (a) 153                                                              (b) 144

            (c) 157                                                              (d) 127

            (e) None of these

Ans.     (a)

            Explanation:

           

           

            Therefore, option (a) is correct.

 

Addition of Three Numbers

            Let?s understand it through the following examples:

 

•      Example:

           

            Trick:

           

 

Addition of Four Numbers

This addition also goes as the previous additions, except 4 numbers are involved in it.

            Let?s see an example given below:

 

•      Example:

\[[\,26\,]+[\,56\,]+[\,22\,]+[\,21\,]=[\,125\,]\]

            Trick: \[[\,26\,]+[\,56\,]+[\,22\,]+[\,21\,]\]

           

 

Important Point

Addition of 4 numbers can also be done by adding two numbers at one time and adding the remaining in the next time. Finally we add the results of both the additions.

 

Let's see:

 

Step I

Add

 

Step II

Add

 

Step III:

Add Step I + Step II

Thus this approach is also very useful while adding  numbers.

 

Addition of Five Numbers

For the addition of five numbers follow the rules given below:

Step I: Add the 1st three numbers.

Step II: Add the remaining two numbers.

Step III: Add step I & step II.

 

•      Example:

\[[\,26\,]+[\,21\,]+[\,15\,]+[\,34\,]+[\,58\,]=[\,154\,]\]

            To get this result follow the method:

 

Step I:  \[[\,26\,]+[\,21\,]+[\,15\,]\]

             

 

Step II: \[[\,34\,]+[\,58\,]\]

           

 

Step III: Step I + Step II

            \[[\,62\,]+[\,92\,]\]

 

           

 

Addition of Figures

Numbers are: \[[\,1\,],\,\,[\,2\,],\,\,[\,3\,],\,\,[\,4\,],\,\,[\,12\,],\,\,[\,54\,]\]etc.

Figures are: \[[\,17\,]\] pencils, \[[\,5\,]\] coins, \[[\,50\,]\] ice creams etc.

 

Thus when a number represents something it becomes a figure.

Addition of figures is done in the same way as the addition of numbers.

 

•      Example:

            \[[\,40\,]\] rupees + \[[\,35\,]\] rupees = \[[\,75\,]\] rupees.

Trick:

                \[[\,40\,]\] rupees + \[[\,35\,]\] rupees.

           

 

•     Example:

            \[[\,35\,]\] homes + \[[\,49\,]\] homes + \[[\,21\,]\] homes = \[[\,105\,]\] homes.

 

Trick:

           

 

Addition of Images

Addition of images means grouping of more than one images into a single group.

 

•      Example:

\[[\,00\,]+[\,0000\,]+[\,0\,]=[\,0000000\,]\]

 

•      Example:

           

In the 2nd example we add group of \[[\,6\,]\] faces with group of \[[\,3\,]\] faces and get the result as the group of \[[\,9\,]\] faces.

 

Word Problems

This topic means language based problems on addition.

 

•      Example:

Helena studies two hours in the morning and two hours in the evening, every day. How many hours she studies in a day?

Explanation: Add the study hour of Helena as  hours. Thus Helena studies  hours in a day.

                      

•      Example:

In a park there are  trees,  creepers and  climbers. How many plants are there in all in the park?

            Explanation: Total number of plants =  plants,