How to Multiply Decimals

We multiply decimals in our daily life as every calculation we come across aren’t whole numbers. We may have to calculate marks and percentages in our school exams, or quantities of food items when we go to the market. Let us learn how to multiply decimals.

Steps for Multiplying Decimals

1. Multiply the decimals such that there is no decimal point. Write the product.
2. Count the number of digits after the decimal point of both multiplying decimal numbers.
3. Put the decimal points in the product after that many numbers.

Let us take another example of a long multiplication as shown below.

Multiply: 9.526 × 2.6

Solution:

9.526 × 2.6
Here the total number of decimal places:
3 + 1 = 4
Multiplying, ignoring the decimal points
9526 × 26
= 247676
Now count the total decimal places and put the point.
= 24.7676

Multiply: 2.53 × 2.6.

Solution:

Multiplying Decimals with Whole Numbers

When we multiply a whole number with a decimal, we only consider the decimal places for the decimal number. So, the decimal places in the product will be the same as in the decimal mulitplying factor. An example is shown below where we multiply 72, a whole number, with a decimal 3.6.

We mentally imagine 72 as 72.0. Since there is only one digit after the decimal point in 3.6, we straight away put the decimal point in the product by counting one digit from the right, i.e., 2. The product comes out to be 259.2

Let us solve an example involving multiplication of whole number and decimals.

Multiply: 16 × 7.24

Solution:

16 × 7.24
Here the total number of decimal places:
0 + 1 = 1
Multiplying, ignoring the decimal points
16 × 724
= 11584
Now count the total decimal places and put the point.
= 115.84