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The procedure is repeated at the second digit, with the next quotient digit 7
( 7 ≡ 1*7 mod 10 ), subtracting 7*543=3801 , leaving 325800. And finally at
the third digit with quotient digit 6 ( 8*7
mod 10 ), subtracting 6*543=3258 leaving 0.
So the quotient is 678. Notice however that the multiplies and subtractions don’t need to extend past
the low three digits of the dividend, since that’s enough to determine the
three quotient digits.