Page 62 - Maths Skill - 3

60 Maths

3. Find the missing factor for each of the following.

(a) 4 × = 36 (b) 4 × = 24 (c) × 8 = 64

(d) 5 × = 40 (e) 7 × = 35 (f) × 9 = 18

Properties of Multiplication

� When two or more numbers are multiplied in any order, their product always
remains the same.

For example, 5 × 7 = 35 and 7 × 5 = 35

Thus, 5 × 7 = 7 × 5

� When a number is multiplied by 1, the product is always the number itself.
For example, 5 × 1 = 5; 24 × 1 = 24; 165 × 1 = 165

� When a number is multiplied by zero, the product is always zero.
For example, 5 × 0 = 0; 36 × 0 = 0; 1125 × 0 = 0

Exercise 5.2

Fill in the blanks by using the properties of multiplication.

(a) 1 × 1256 = (b) × 125 = 125 (c) × 15 = 0

(d) 0 × 24 = (e) 4 × 0 = (f) 175 × = 175

(g) 19 × 6 = 6 × (h) 12 × = 7 × 12 (i) 7 × 5 = × 7

Multiplying 3-digit Number by 1-digit Number

Without Regrouping

Let us multiply 234 by 2.
Arrange the numbers as per their place values and follow these steps:

Step 1: Start at ones place. Step 2: Multiply 3 tens by 2.
Multiply 4 ones by 2. 3 tens × 2 = 6 tens

4 ones × 2 = 8 ones Write 6 under tens column.
Write 8 under ones column. H T O

H T O 2 3 4
2 3 4 × 2
× 2 6 8
8