Adding and Subtracting Decimals August 20, 2013 Sixth Grade Math

Essential Question How do I add and subtract decimals using the standard algorithm for each operation?

To add decimals Step 1: Line up the decimal points so that the same place values are lined up. Use zeros as place holders. **When adding a whole number and a decimal, put a decimal point behind the whole number. Step 2: Add from right to left, starting with the smallest place value. Place a decimal point in the answer directly below the other decimal points.

Example Line up the decimal points __________________________ Add the columns. 1.03

Example Line up the decimal points _____________________________ Add the columns Don’t forget to put a decimal point behind the whole number and add zeros to hold the place values. Don’t forget to put a decimal point behind the whole number and add zeros to hold the place values.

To subtract decimals Step 1: Line up the decimal points so that the same place values are lined up. Use zeros as place holders. **When subtracting a whole number and a decimal, put a decimal point behind the whole number. Step 2: Subtract from right to left, starting with the smallest place value. Place a decimal point in the answer directly below the other decimal points.

Example – 0.49 Line up the decimal points __________________________ Subtract the columns

Example 2 36 – Line up the decimal points. Don’t forget to put a decimal point behind the whole number and add zeros to hold the place values. Don’t forget to put a decimal point behind the whole number and add zeros to hold the place values Subtract the columns. Regroup if necessary

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