Multiplication Class 2 Notes Maths

What is Multiplication?

• Multiplication is a fast way to add the same number again and again.

• Instead of writing 4 + 4 + 4, we can say “3 times 4.”

Think of it like this:

• You have 3 baskets.
• Each basket has 4 apples.
  
• To find the total, you could add: 4 + 4 + 4.
• Or you can multiply: 3 × 4 = 12.

• So, 3 groups of 4 apples give 12 apples in all!

  Multiplication helps us count groups quickly and easily.

Multiplication as Repeated Addition

Adding the same number again and again is called repeated addition.
Example: Aryan has 5 tricycles. Each tricycle has 3 wheels. What is the total number of wheels in all the tricycles?

There are 3 + 3 + 3 + 3 + 3 = 15 wheels in all.
3 is repeatedly added 5 times.
We write it as 3 × 5 = 15.
We say, 5 times 3 is 15 or 5 threes are 15 or 3 into 5 is 15.

Repeated addition of the same number is called multiplication.
4 × 2 = 8 is a multiplication fact.
‘×’ is the sign of multiplication.
So, instead of adding the same number again and again, we can multiply to find out the answer.

Study the following.
Here are 4 baskets with 2 mangoes in each.

How many mangoes are there in all?
By adding repeatedly, we find that there are 2 + 2 + 2 + 2 = 8 mangoes in all.
Using multiplication,
we write 4 × 2 = 8 and read as 4 times 2 are 8 or 4 multiplied by 2 is 8.

Multiplication on the Number Line

We already know that multiplication is repeated addition. We can represent multiplication on the number line by skip counting.

Let us find 3 × 5.

3 × 5 means take 3 skips of 5s starting from 0, as shown above.

We have reached 15 after 3 skips of 5s. So, 3 × 5 = 15.

Properties of Multiplication

Order Property of Multiplication

There are 2 rows of 5 pineapples each.
The multiplication fact becomes 2 × 5 = 10.
We can also think that there are 5 columns of 2 pineapples each.
Now, the multiplication fact becomes 5 × 2 = 10.
Since the product is the same in both cases,
we have 2 × 5 = 5 × 2 = 10.
We may multiply the numbers in any order, the product would be the same.
This basic property of multiplication is called the order property of multiplication.

Multiplicative Property of 1

5 groups of 1 = 5 × 1 = 1 + 1 + 1 + 1 + 1 = 5
1 group of 5 = 1 × 5 = 5
So, 5 × 1 = 1 × 5 = 5.
We can show the above results using a number line.

Any number multiplied by 1 equals that number. This is called the multiplicative property of 1.

Multiplicative Property of 0

There are 3 empty baskets, which means 3 groups of nothing.
So, 3 × 0 = 0.
Also, by order property 3 × 0 = 0 × 3 = 0.
Thus, we have
Any number multiplied by 0 equals 0. This is called the multiplicative property of 0.

Multiplication Tables

You have already learnt and memorised tables of 1 to 5 in Class 1. Let us revise the same.

Multiplication Table of 2
Count and build the table of 2.

Multiplication Table of 3

Count and build the table of 3.

Multiplication Table of 4

Count and build the table of 4.

Multiplication Table of 5

Count and build the table of 5.

Multiplication Table of 6

Count and build the table of 6.

Multiplication Table of 7

Count and build the table of 7.

Multiplication Table of 8

Count and build the table of 8.

Multiplication Table of 9

Count and build the table of 9.

Multiplication Table of 10

Count and build the table of 10.

Problems Based on Real-Life Situations

Example 1: There are 6 bananas in a bunch. There are 9 bunches. How many bananas are there in all?

Sol: 
Bananas in 1 bunch = 6
Bananas in 9 bunches = 9 × 6 = 54

Example 2: Reena has 5 pairs of gloves, 3 pairs of socks and 8 pairs of bangles. How many items are there in total?

Sol: 

Number of gloves = 5 pairs = 5 × 2 = 10
Number of socks = 3 pairs = 3 × 2 = 6
Number of bangles = 8 pairs = 8 × 2 = 16
Total number of items = 10 + 6 + 16 = 32

Multiplication in Column Form

• Multiplication in Column Form is a way to multiply small and big numbers step by step by writing them neatly in columns.
• Let's understand with the help of an example.

Example 1: Multiply 6 x 3.
Sol: Let's learn multiplication step-by-step.

Step 1: Write the numbers in columns.

Step 2: Multiply 6 × 3 = 18.

Step 3: Write 8 in the one's place and carry over 1 (for 10) to the tens place. 

Example 2: Multiply 23 x 3. 
Sol:

Step 1: Write the numbers in columns.

Step 2: Multiply the number in the ones place (3 × 3 = 9)

Step 3: Multiply the number in the tens place (2 × 3 = 6)

Column multiplication helps you multiply neatly and step by step!