When comparing decimal numbers, place the numbers in columns according to the value in each digit. Make sure that the decimal point for each number are all in the same column.
If the decimal number is less than zero, then place a zero to the left of the decimal point eg write .035 as 0.035.
Which is worth the most: a pen worth £2.99; a chocolate bar worth 69p, or a 10p coin?
Change the chocolate bar and the coin to be in pounds, so that 69p becomes £0.69 and 10p becomes £0.10.
Place the numbers in a table, making sure that the decimal numbers are all lined up.
The highest number in the units column is the 2 from £2.99.
| 2 | . | 9 | 9 | The 2 in the units column is the highest unit |
| 0 | . | 6 | 9 | The 6 in the tenths column is the highest of the remaining two numbers |
| 0 | . | 1 | 0 |
Answer: The pen, worth £2.99
Place these numbers in order with the highest first: 23.4, 105, 10.09 and 0.01.
Write the numbers in a table, making sure that the decimal points are lined up.
Examine each column, working from left to right, finding the highest numbers depending upon their highest column value.
| 2 | 3 | . | 4 | The 2 in the tens column makes number second highest | |
| 1 | 0 | 5 | . | 0 | The 1 in the hundreds column is highest |
| 1 | 0 | . | 9 | The 1 in the tens column is higher than nothing in the tens column | |
| 0 | . | 1 |
and in order:
| 1 | 0 | 5 | . | 0 | |
| 2 | 3 | . | 4 | ||
| 1 | 0 | . | 9 | ||
| 0 | . | 1 |
Answer: 105, 23.4, 10.9, 0.1
See also Ordering Numbers and Ordering Fractions