Solution: Align the two addend units, and then add the numbers in the same counting unit respectively. When the addition result exceeds 10, it will reach the high position of 1, and the addition of the high position needs to accumulate the low position result of 1.
Problem solving process:
Step 1: 9+2= 1 to the high position, 1.
Step 2: 8+6+ 1=5 to the high position, 1.
Step 3: 7+ 1+ 1=9.
According to the above calculation steps, the calculation result is 95 1.
Checking calculation: 95 1- 162=789.
Extended data (check result): align the units of the minuend and the minuend, and then subtract them from the numbers in the corresponding counting units respectively. If the subtraction is not enough, you need to borrow 1 from the high position, and then calculate the results in turn. If the subtraction is less than the minuend, add a negative sign to the final result of subtraction. Fractional subtraction can refer to the integer subtraction step;
Problem solving process:
Step 1: High-level borrowing 1 1-2=9.
Step 2: High-level borrowing 15-6- 1=8.
Step 3: 9- 1- 1=7
According to the above calculation steps, the comprehensive calculation result is 789.
If in doubt, please ask questions. If satisfied, please adopt them.