155×26=4030, calculated as follows:

1, the first type: exchange the positions of two factors for recalculation;

26× 155=4030, correct.

Divide the product by one factor to see if it is equal to another factor.

4030÷26= 155, correct; 4030- 155 = 26, correct.

Extended data

1. Multiplies the number on the two-digit number by another factor, and the last digit of the number is aligned with the single digit of the two-digit number.

2. Multiply the number on the ten digits by another factor to get that the last digit of the number is aligned with the ten digits of the two digits.

3. Then add up the multiplied numbers twice.

There is a zero at the end of the factor: multiply the number before zero first, then see how many zeros there are at the end of the multiplier, and add a few zeros at the end of the multiplied number.

Note: There are several zeros at the end of two factors, and at least several zeros at the end of the product.

Multiply three digits with zero at the middle or end of the factor by two digits: the middle of the factor is a multiple of zero; If there is a zero at the end, align the last digit of the number in front of the two factors, multiply it by the number in front of zero, and then it will return to zero, and several zeros will return to several zeros.