In the division with remainder in grade two, the remainder must be less than the divisor. The largest remainder is less than the divisor 1, and the smallest remainder is 1.

1. In division with remainder, the remainder must be less than the divisor. In the division formula, dividend-divisor = quotient ... remainder, where the remainder must be less than divisor. Assuming that the remainder is greater than the divisor and the quotient is not the largest, then the remainder must be less than the divisor in the division with remainder.

2. If the remainder is 3, the minimum divisor is 4, if the divisor is 3, the maximum remainder is 2, if the remainder is 3, the minimum divisor is 3+ 1=4, if the divisor is 3, the maximum divisor is 3-1= 2; So the answer is 4.