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Squaring special numbers (9's and final 2)
Choose a number with repeating 9's and a final 2.
The square is made up of:
one fewer 9 than there are repeating 9's
84
the same number of 0's as there are 9's in the square
A final 64
Example:
If the number to be squared is 9992:
The square has:
one fewer 9 than the
repeating 9's: 9
9
84
8 4
same number of 0's as 9's
in the square
0 0
a final 64
6 4
So 9992 x 9992 = 99840064.
See the pattern?
If the number to be squared is 999992:
The square has:
one fewer 9 than the
repeating 9's: 9 9 9 9
84 8
4
same number of 0's as 9's
in the square 0
0 0 0
a final 64
6 4
So 999992 x 999992 = 999984000064.
With a little practice you will be finding these huge products with ease.