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Learn to add and subtract decimals. Before you Add or Subtract LINE UP THE DECIMALS!!. –0.4619 –0. 5. Round to the nearest whole number. The sum is about 10. Round to the tenths. Align. Subtract. Example 1) Estimate by rounding to the indicated place value. A. 6.09 + 3.72; ones
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Before you Add or Subtract LINE UP THE DECIMALS!!
–0.4619 –0.5 Round to the nearest whole number. The sum is about 10. Round to the tenths. Align. Subtract. Example 1) Estimate by rounding to the indicated place value. A. 6.09 + 3.72; ones B. 8.898 – 0.4619; tenths 6.09 + 3.72 6 + 4 = 10 8.898 8.9 8.4
Example 2) Find each sum or difference. A. 0.975 + 3.8 B. 0.22 + 15.607 + 9.7
Helpful Hint You can place any number of zeros at the end of a decimal number without changing its value.
Substitute 3.8 for x. Align the decimal points. Use zeroes as placeholders. Subtract. Place the decimal point. Example 3) Evaluate 6 – x for each value of x. x = 3.8 6 – x 6 –3.8 6.0 – 3.8 2.2
Substitute 2.9765 for x. Align the decimal points. Use zeros as placeholders. Subtract. Place the decimal point. Example 4) Evaluate 6.73 – x for each value of x. x = 2.9765 6.73 – x 6.73 – 2.9765 6.7300 –2.9765 3.7535