What you need to know

Things to remember:

  • Multiplication be used in the regular way.
  • We can split the decimal up and multiply individually, adding the pieces back together at the end.

What is 5\times2.39?

We can do this in two ways.

Way 1: Multiply each place value individual.

Step 1: Find the value of each number.

2 \rightarrow Units \rightarrow 2\times1=2

3 \rightarrow Tenths \rightarrow 3\times0.1=0.3

9 \rightarrow Hundredths \rightarrow 9\times0.01=0.09

Step 2: Multiply the value represents by each number by the whole number.

5\times2=10

5\times0.3=1.5

5\times0.09=0.45

 

Step 3: Add these together.

 

 

Way 2: Column Multiplication

 

 

5\times2.39=11.95

 

So, it doesn’t really matter which way we do this, we’ll get the same answer either way!

Example Questions

Question 1: Use Way 1 to find the value of 7\times4.27

Answer

Step 1: Find the value of each number.

4 \rightarrow Units \rightarrow 4\times1=4

2 \rightarrow Tenths \rightarrow 2\times0.1=0.2

7 \rightarrow Hundredths \rightarrow 7\times0.01=0.07

Step 2: Multiply the value represents by each number by the whole number.

7\times4=28

7\times0.2=1.4

7\times0.07=0.49

Step 3: Add these together.

 

 

7\times4.27=29.89

Question 2: Use column multiplication to find the value of 8\times2.36

Answer

 

8\times2.36=18.88