Use Place Value to Solve Problems Involving Decimals

We can use place value to help us solve problems like this:

 

Which is bigger: 4.52 or 4.7?

 

Let's write the numbers in a place value chart. 

 

 

We can see they both have 4s in the ones column, so we move along to the tenths. We know 7 is bigger than 5, so the 2nd number is bigger.

 

4.7 is bigger than 4.52

 

 

How do we calculate 61.45 + 0.23?

 

We must line up the decimal points underneath each other:

 

 

Then we can carry out simple addition as we would with whole numbers, starting with the right-hand column first:

 

 

So 61.45 + 0.23 = 61.68

 

Are you ready to have a go?