Squaring
numbers close to base 1000
10252
=?
Notice that 1025 is
close to base 1000. So,
1) Find the surplus or deficit from base 1000.
It
is (1025–1000=) 25 surpluses.
2) Since
1025 is 25 more than base 1000, so add 25 to the entire number, which is
1025+25 = 1050. Write 1050 as the first part of the answer.
3) Now,
since 1000 has 3 zeros so, 3 more digits to go. Find the square of surplus 25
which is 625. Write 625 as the last
3 digits of the answer.
So, our answer is 1,050,625.
Another example, 9852 =?
985 is (1000-985=) 15
less than the base 1000.
Subtract 15 from 985,
which is 970.
Square of 15 is 225.
Write 225 for the last 3 places.
So, our answer is
970225.
Further example, 9962 =?
996 is (1000-996=) 4
less than the base 1000.
Subtract 4 from 996,
which is 992.
Square of 4 is 16.
So, write 016 for the last 3 places. (Notice the extra ‘0’)
So, our answer is
992016.
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