Add or Subtract 1,000 With Four-Digit Numbers

When we add 1,000 to a four-digit number, we must increase the digit in the thousands column by 1.

 

Here is the number 1,623 shown on an abacus.

Notice how the abacus says units. Units are another word for ones. 

 

 

When we add 1,000 we add an extra number to the thousands column.

 

 

1,623 + 1,000 = 2,623

 

Example

Add 1,000 to:

5,028

 

Answer

We increase the 5 in the thousands column by 1 to get 6 in that column.

5,028 + 1,000 = 6,028

 

When we subtract 1,000 from a four-digit number, we must decrease the digit in the thousands column by 1.

Here is the number 4,705 shown on an abacus.

  

 

When we subtract 1,000 from it, we take away one number from the thousands column.

 

 

4,705 - 1,000 = 3,705

 

Example 1

Subtract 1,000 from:

5,097

 

Answer

We decrease the 5 in the thousands column by 1 to get 4 in that column.

5,097 - 1,000 = 4,097

 

Example 2

Subtract 1,000 from:

1,060

 

Answer

We decrease the 1 in the thousands column by 1 to get 0 in that column.

Remember to leave off any zeros on the left-hand side of a number.

1,060 - 1,000 = 0060 = 60

 

Does that make sense?

 

 

Let's practise this in the questions that follow.