As shown in the figure:
1, 4+3+8= 15. Draw a horizontal line under the formula of 4+3 to get the answer 7, then write the answer 7 under the horizontal line, and then use the answer 7+8 to get the final result 15.
2. 13+4-9=8. Draw a horizontal line under the formula 13+4 to get the answer 17, then write the answer 17 under the horizontal line, and then use the answer 17-9 to get the final result 8.
3. 17-5-8=4. Draw a horizontal line under the formula of 17-5 to get the answer 12, then write the answer 12 under the horizontal line, and then use the answer 12-8 to get the final result 4.
4. 12-7+6 = 1 1. Draw a horizontal line under the formula12-7 to get the answer 5, then write the answer 5 under the horizontal line, and then use the answer 5+6 to get the final result1/kloc-0.
This is the application of line drawing calculation. The calculation of drawing lines improves the calculation ability and reduces the errors of addition and subtraction.
Extended data:
Addition and subtraction are not complicated.
1. Add or subtract the first two numbers to get a sum or difference.
2. Add or reduce the sum or difference of the previous step to the last number in the addition and subtraction formula, and the result is the final result.
3. Addition and subtraction are calculated from left to right.