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E:\Working\Orange_Education\Math_Genius_5\Open_Files\CHAP_02
\\October 8, 2025 12:09 PM Bharat Arora P-9 Reader _________________________ Date: ___________________74
When a number is multiplied by 100, we put two zeros to the right side of the number.
examples: (a) 643 × 100 = 64300 (b) 8572 × 100 = 8,57,200
When a number is multiplied by 200, 300, 400, ..., 900, we multiply the number by 2, 3,
4, ..., 9 respectively and then put two zeros to the right side of the product so obtained.
examples: (a) 78 × 400 = 31200 (b) 273 × 800 = 2,18,400
When a number is multiplied by 1000, we put three zeros to the right side of the number.
examples: (a) 15 × 1000 = 15,000 (b) 198 × 1000 = 1,98,000
When a number is multiplied by 2000, 3000, 4000, ..., 9000, we multiply the number
by 2, 3, 4, ..., 9 respectively and then put three zeros to the right side of the product
so obtained.
examples: (a) 24 × 3000 = 72,000 (b) 571 × 7000 = 39,97,000
Multiplication of large numbers
Larger numbers are multiplied in the same way The number to be multiplied is called
as smaller numbers. To multiply large numbers, the multiplicand.
we follow the steps.
The number by which we multiply is
Step 1: Write the numbers in columns. called the multiplier.
Step 2: Start multiplication from the ones place. The result of the multiplication is called
Step 3: Move to the tens place, hundreds place their product.
and so on.
Step 4: Add the carry over if any.
example 1: Multiply 6172 by 435.
Solution:
Step 1: Expand the multiplier.
435 = 400 + 30 + 5 TL L tth th H T O
Step 2: Multiply by the ones. 6 1 7 2
6172 × 5 = 30,860 × 4 3 5 400 + 30 + 5
Step 3: Multiply by the tens. 3 0 8 6 0 6172 × 5
6172 × 30 = 1,85,160 + 2 1 8 5 1 6 0 6172 × 30
4
6
0
0
8
8
6172 × 400
Step 4: Multiply by the hundreds. 2 6 8 4 8 2 0
6172 × 400 = 24,68,800
Step 5: Add all the partial products.
30,860 + 1,85,160 + 24,68,800 = 26,84,820
Thus, 6172 × 435 = 26,84,820.
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