When calculating the division vertically, start from most significant bit, such as: 42 from most significant bit 4; If it can't be divisible, for example, 4 can't be divisible by 7, then use the highest bit and the next bit to synthesize a number to be divisible until it can be divisible by the divisor.

For example, if 4 is not divisible by 7 in 42, then 4 and 2 are combined into a number. If 42 is divided by 7, the quotient is 6.

Division formula: dividend-divisor = quotient; Dividend quotient = divisor; Quotient divisor = dividend; There is a remainder: dividend γ divisor = quotient ... remainder (where the remainder is less than divisor), divisor× quotient+remainder = dividend.

The nature of the division operation:

In division calculation, if a number is divided by (or multiplied by) a number and then multiplied by (or divided by) the same number, the number remains unchanged. For example: 68÷ 17× 17=68 (or 68× 17÷ 17=68).

In division calculation, the product of several numbers is divided by a number, so that any factor in the product can be divided by this number and then multiplied by other factors. For example: 8×72×4÷9 = 72÷9×8×4 = 256.