Subtracting Decimals

The methods of subtracting decimals is almost the same as subtraction of integers. The only difference is that decimal subtraction has the decimal point. After subtracting the numbers and writing the answer count the number of digits to the right of the decimal point of the number having the most decimal positions. The decimal point is always positioned this number of digits from the right-most digit of the answer.

23.65

− 5.43

27.22

The most digits to the right of the decimal point for any number is 2. They are 6 and 5 or 4 and 3.

47.39

− 16.742

30.648

The most digits to the right of the decimal point for any number is 3. They are 7, 4 and 2.

12.309

− 6.742

5.567

The most digits to the right of the decimal point for any number is 3. They are 3, 0, and 9 or 7, 4 and 2.

13.230

− 5.74

7.49

Decimal positions that are zeros on the far right of added numbers are not counted.

The most digits to the right of the decimal point for any number is 2. They are 2 and 3 or 7 and 4.

The reason far right zeros are not counted for decimal point positioning is the zeros have no value for the number and can be removed:

13.23 is the same value as 13.230 or 13.2300

If the zero isn’t a far right zero it has place value:

13.023 is not equal to 13.203 is not equal to 13.230.

.023 = 23/1,000

.203 = 203/1,000

.230 = 23/100

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