In ascending order (smallest to greatest) the numbers are: You can use a number line to order decimals too. This number line is split into tenths and has the numbers 0.6, 0.4, and 0.9 labelled on it.

This number line shows how this works for decimals between 1.6 and 1.7. A place value chart can be really helpful when rounding decimals. They help you see the value of each digit within a number.