Multiplication Tricks
Magic of Number 1
- 1 X 1 = 1
- 11 X 11 = 121
- 111 X 111 = 12321
- 1111 X 1111 = 1234321
- 11111 X 11111 = 123454321
- 111111 X 111111 = 12345654321
- 1111111 X 1111111 = 1234567654321
- 11111111 X 11111111 = 123456787654321
- 111111111 X 111111111 = 12345678987654321
- 1111111111 X 1111111111 = 1234567900987654321
Example 1: Lets multiply 11 and 11
STEP 1: No. of digits in multiplier = 2
STEP 2: Write in descending order upto 1. i.e 21[RHS Answer]
STEP 3: Now,No. of digits in multiplier - 1 .ie.(2-1)=1
STEP 4: write it in ascending order upto output of STEP 3.i.e 1[LHS Answer]
STEP 5: Combine STEP 2 and STEP 4 together.i.e 121
Example 2: Lets multiply 1111 and 1111
STEP 1: No of digits in multiplier = 4
STEP 2: Write in descending order upto 1. i.e 4321[RHS Answer]
STEP 3: Now,No. of digits in multiplier - 1 .ie.(4-1)=3
STEP 4: write it in ascending order upto output of STEP 3.i.e 123[LHS Answer]
STEP 5: Combine STEP 2 and STEP 4 together.i.e 1234321
Example 3: Lets multiply 1111111111 and 1111111111
STEP 1: No of digits in multiplier = 10
STEP 2: Write in descending order upto 1. i.e 10/987654321, here carry is generated and it will move forward.[RHS Answer]
STEP 3: Now,No. of digits in multiplier - 1 .ie.(10-1)=9
STEP 4: write it in ascending order upto output of STEP 3.i.e 123456789 + add carry(1)=123456790[LHS Answer]
STEP 5: Combine STEP 2 and STEP 4 together.i.e 1234567900987654321