MathKits - Addition and Subtraction

1. Addition

Let's go through the process of adding two numbers step by step.

Step 1: Line up the numbers by their place value. Start from the right (ones place).

Example: Add 356 + 489

Step 1:

                356
              + 489

Step 2: Start with the ones column (rightmost). Add 6 + 9. If it’s greater than 9, carry the tens place to the next column.

Example: 6 + 9 = 15. Write 5 and carry over 1.

                Carry: 1
                356
              + 489
            -----------
                5

Step 3: Now add the tens column. 5 + 8 = 13, plus the carried over 1 makes 14. Write 4 and carry over 1.

Example: 5 + 8 = 13, plus the carry over 1 = 14. Write 4 and carry over 1.

                Carry: 1
                356
              + 489
            -----------
               45

Step 4: Now add the hundreds column. 3 + 4 = 7, plus the carry over 1 makes 8. Write the result.

Example: 3 + 4 = 7, plus the carry over 1 = 8. Write 8.

                356
              + 489
            -----------
               845

Now let's look at how to subtract two numbers step by step.

Step 1: Line up the numbers by their place value, just like in addition.

Example: Subtract 700 - 322

Step 1:

                700
              - 322

Step 2: Start with the ones column. Can you subtract 2 from 0? No, so borrow 1 from the tens column.

Example: Borrow 1 from the tens column, making it 9. The ones column becomes 10. Now subtract 2 from 10.

                700
              - 322
            -----------
                10 (after borrowing)

Step 3: Move to the tens column. After borrowing, you are left with 9. Now subtract 2 from 9.

Example: 9 - 2 = 7. Write 7 in the tens place.

                700
              - 322
            -----------
                70

Step 4: Finally, subtract the hundreds column. 6 - 3 = 3.

Example: 6 - 3 = 3.

                700
              - 322
            -----------
               378