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Squaring special numbers (9's and final 3)
Choose a number with repeating 9's and a final 3.
The square is made up of:
one fewer 9 than there are repeating 9's
86
the same number of 0's as there are 9's in the square
A final 49
Example:
If the number to be squared is 9993:
The square has:
one fewer 9 than the
repeating 9's: 9
9
86
8 6
same number of 0's as 9's
in the square
0 0
a final 49
4 9
So 9993 x 9993 = 99860049.
See the pattern?
If the number to be squared is 999993:
The square has:
one fewer 9 than the
repeating 9's: 9 9 9 9
86 8
6
same number of 0's as 9's
in the square 0
0 0 0
a final 49
4 9
So 999993 x 999993 = 999986000049.
Using this pattern you will be able to square these large numbers with ease.