Finally, add up the results and the result is: 4200.
Reflections on solving problems in vertical calculation;
1. Align the last digit of the two multipliers first.
2. Then use the second multipliers respectively, and multiply each bit with one multiplier in turn, starting from the last bit.
3. Finally, the calculation results are accumulated into products.
4. If the multiplier is decimal, you can expand the corresponding multiple first, and then reduce the product by the corresponding multiple.
Law of division:
When an integer A is divided by an integer b (b≠0), the quotient is exactly an integer with no remainder. We say that A is divisible by B (that is, B is divisible by A). When the quotient is an integer or a finite decimal and the remainder is 0, we say that A is divisible by B (that is, B is divisible by A). Here, a and b can be natural numbers.
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.