Multiplication Tricks
Multiplication of a whole number with the multiples of 10:
Example 1:
Multiply 2100 by 400.
Solution:
Step 1: Multiply 21 by 4
21 × 4 = 84
Step 2: Total number of zeros in each of the factor = 4.
Step 3: Add 4 zeros in the product 84.
840000
Therefore, 21 × 4 = 8,40,000.
Example 2:
Multiply 100 by 1000.
Solution:
Step 1: Multiply 1 by 1
1 × 1 = 1
Step 2: Total number of zeros in each of the factor = 5.
Step 3: Add 5 zeros in the product 1.
100000
Therefore, 100 × 1000 = 1,00,000.
Multiplication of two digits number by a two digits number:
Step 1: Multiply the unit digit of both the numbers.
Step 2: Multiply the unit digit of multiplier by the ten digit of multiplicand and the ten digits of multiplier by the unit digit of multiplicand. Add them together.
Step 3: Multiply the ten digits of both the number.
Example:
Multiply 57 by 62.
Solution:
Multiplication of two digits number by a two digits number when the ten digits are same and the sum of unit digit is 10:
Step 1: Multiply both the unit digits.
Step 2: Multiply the ten digits by the succeeding digit.
Step 3: Combine both the results.
Example:
Multiply 27 by 23.
Solution:
The sum of unit digit is 10 = (7 + 3).
Multiply 3 by 7 = 3 × 7 = 21
The digit in tens place is 2. The successor of 2 is 3.
Multiply 2 by 3 = 2 × 3 = 6.
The solution is 621.
Multiplication of three digits number by a two digits number:
Example:
Multiply 157 by 23.
Solution:
Multiplication of three digits number by a three digits number:
Example:
Multiply 517 by 216.
Solution:
Therefore, 517 × 216 = 1,11,672.
Multiplication of three digits number by a three digits number when the ten digits and hundred digits are same and the sum of unit digit is 10:
Step 1: Multiply both the unit digits.
Step 2: Multiply the ten and the hundred digits by the succeeding digit.
Step 3: Combine both the results.
Example:
Multiply 277 by 273.
Solution:
The sum of unit digit is 10 = (7 + 3).
Multiply 3 by 7 = 3 × 7 = 21
The digit in tenths and the hundreds place is 27. The successor of 27 is 28.
Multiply 27 by 28 = 27 × 28 = 756.
The solution is 75,621.
Multiplication Tricks by Numbers
Rule for Multiplying by 9:
Example 1:
Multiply 45 by 9
Solution:
Step 1: Multiply 45 by 10.
45 × 10 = 450
Step 2: Subtract 45 from 450.
450 – 9 = 405
Rule for Multiplying two digits number by 11:
Write the sum of the digits of the number in between the digits.
Example 1:
Multiply 27 by 11
Solution:
Rule for Multiplying three digits number by 11:
Example 2:
Multiply 157 by 11.
Solution:
Admissions Open for 2025-26