It is better to teach than not to teach, and the person who gave the question doesn't know much about the textbook. Other students didn't teach badly, but they didn't do well in the exam. It is better not to teach students under 20 in the first semester of senior one, so it is easier to train students' oral expression ability. Two digits plus one digit and two digits plus two digits must be taught in the second semester.
Extended data:
The remainder has the following important properties (A, B and C are all natural numbers):
(1) The absolute value of the difference between the remainder and the divisor is less than the absolute value of the divisor (applicable to the real number field);
(2) Dividend = divisor × quotient+remainder;
Divider = (dividend-remainder) ÷ quotient;
Quotient = (dividend-remainder) divider;
Remainder = dividend-divisor × quotient.
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