Put Decimals In Order Of Size
Warm Up
Which is greater 0.9 or 0.12 ?
It is easier to see which is greater if we have the same number of decimal places in each number.
The most decimal places that we have in a number here is 2.
So, write each number with two decimal places using 0's where necessary.
0.90 0.12
Just as 90 is greater than 12 then 0.90 is greater than 0.12
so 0.9 is greater than 0.12
Example of an exam type question
Place these decimals in ascending order of size. 
0.12 
0.6 
0.312 
0.181 
The most decimal places in any number is 3 so write all of the numbers with 3 decimal places. 
0.120 
0.600 
0.312 
0.181 
We need the numbers in ascending order of size so write (1) under the smallest then (2) under the next and so on. 
(1) 
(4) 
(3) 
(2) 
Now write the original numbers in the order given by (1), (2), (3) and (4) 
0.12 
0.181 
0.312 
0.6 
