Ten More or Ten Less than a Number

To find 10 more than a number, add 1 to the digit at the tens place.

To find 10 less than a number, subtract 1 from the digit at the tens place.

For example: Let's find 10 less than the number 47.

This number can be written in the place value table as:

Notice that there are four tens in the number 47.
 

To find 10 less than 47, subtract 1 from the digit at its tens place.

4 – 1 = 3

So, 10 less than the number 47 is 37.