Christina B. answered • 03/13/19
Experienced, Positive, and Effective Tutor with an M.Ed.
Hi, Davis!
The good news is that multiplication works the same, whether there are decimals in the numbers or not. Let's do a sample problem to take a look.
Suppose you wanted to find 2.3 x 5. You would set it up just like 23 x 5.
2.3
x 5
___
First multiply your ones digits. Then multiply your tens digit by your ones digit.
2.3
x 5
___
5
2.3
x 5
___
115 --> 11.5
Once you have finished your computation, count the number of digits to the right of the decimal point in the factors (2.3 and 5). In this problem, it is only one digit, the 3, that is to the right of the decimal. If one digit is to the right of the decimal in the factors, then one digit is to the right of the decimal in the product. Therefore, we put the decimal in the product between the 1 and the 5. Our final answer is 11.5.
