Multiplication of Numbers in the range of 10,100,1000

Suppose you get to calculate the square of 9997 . Even the thought of approaching the question will run a chill up your spine.
But hey, don't worry. In 2 minutes, you'll be wishing that such calculations DO come in the CAT.
Heres how to approach them :

General Method :

Calculate 104 x 103 :

1.Add the digits exceeding or lesser than 10 or 100 or 1000 , as the case may be :100 +4 + 3 : 107

2. Now, add 'z' zeroes to the above number. where z= 1 , if number is in range of 10's
= 2 , if number is in range of 100's
= 3 , if number is in range of 1000's

So, in this case we add 2 zeroes : 10700

3. Now multiply the numbers 4 and 3 [ in the above case] : 12

4. Add 10700 and 12 : 10712
Hence the answer is 10712

Some more examples :

• Find the square of 9997

1.) Calculate : 1000 -3 - 3 = 9994
2.) Add 3 zeroes : 9994000
3.) Multiply 3 and 3 = 9
4.) Add em : 9994009

• Multiply 112 and 96

1) Calculate : 100 + 12 -4 : 108
2) Add 2 zeroes : 10800
3) Multiply 12 and 4 : 48
4) Add em : 10848


Got it? Wasn't it simple? Now, practice some more so that you get the hang of it. HAPPY MULTIPLICATION!!!