After completing this unit you should be able to:
In this unit we will give a review of some basic operations with decimals. Performing these operations with decimals is like doing them with whole numbers. The difference is the way that you need to keep track of the decimal point. In each section of this unit there is an example that should help remind you of this.
Addition and subtraction of decimals is like adding and subtracting whole numbers. The only thing we must remember is to line up the place values correctly. The easiest way to do that is to line up the decimal points.
In this section we will provide a few examples to remind you of the procedure for adding and subtracting decimals. Look at the examples below, and then read through the detailed examples.



Add the following numbers 1.19 and .16
The answer to this is: 1.19 + .16 = 1.35.





Subtract 1.387 from 12.17.
The answer to this is: 12.17  1.387 = 10.783







When multiplying numbers with decimals, we first multiply them as if they were whole numbers. Then, the placement of the number of decimal places in the result is equal to the sum of the number of decimal places of the numbers being multiplied.
For example, if we multiply 2.3 times 4.5, each number has one digit to the right of the decimal, so each has one decimal place. When they are multiplied, the result will have two digits to the right of the decimal, or two decimal places. Now let's look at a detailed example of multiplying two number with decimals. 
Multiply 12.3 by 3.54.
The answer is 43.542









Division with decimals is easier to understand if the divisor (the dividend is divided by the divisor) is a whole number.





Now let's look at a detailed example of dividing with decimals.
Divide 0.2334 by .004
The answer is 58.35








The decimal point in the result is directly above the decimal point in the dividend. 







