First, pick what you want to do: addition, subtraction, multiplication or division.
Then, pick your level...
Easy - uses one whole number and one decimal number.
Medium - uses two decimal numbers, but with one one or two decimal places.
Hard - uses two decimal numbers with up to four decimal places.
Killer - two decimal numbers with lots of decimal places.
The Decimals Cruncher will keep track of your score. When you move to a new operation (addition, subtraction, multiplication or division), your score will start over again.