Subtraction of decimals works in a similar way to addition. We line up the decimal points in order to line up the place values. Regrouping works just as it did with whole numbers, since each place value is still ten times as much as the place value on its right.
Example: Find the difference 400.5 – 37.25.
The difference 400.5 – 37.25 is 363.25.
Here is a modification of the above standard subtraction algorithm that simplifies the exchanges.
A gas tank contains 13.2 gallons of gas at the beginning of a trip and 5.37 gallons at the end fo the trip. How many gallons of gas were used on the trip?
"Repeating decimals do not end," remarked Dana in his infinite wisdom.
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Date last modified: June 26, 2010.
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