Thinking of solving problems: Four arithmetic rules (calculation in sequence, first multiplication and division, then addition and subtraction, first parenthesis, first power), that is, disjoint operation (recursive equation calculation), should be carried out on the premise of this principle.

Problem solving process:

99× 12+8 1× 12

=(99+8 1)× 12

= 180× 12

=2 160

Extended data \ Calculation result: first align the last digit of two multipliers, then use the second multipliers respectively, starting from the last digit, multiply each digit by one multiplier in turn, and finally accumulate the calculation result into the product. If the multiplier is decimal, the corresponding multiple can be expanded first, and then the product can be reduced by the corresponding multiple;

Problem solving process:

Step 1: 2× 180=360.

Step 2:/kloc-0 /×180 =1800.

According to the above calculation results, it adds up to 2 160.

If in doubt, please ask questions. If satisfied, please adopt them.