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Count Up Method. Subtract by Adding Up. Students make so many errors with this method. The Count Up Method. 1000 - 279 = ?. 279. +1 = 280. + 20 = 300. +700 = 1000. This uses the concept of “difference.” How far is it from 279 to 1000? 7 21. Count Up Method.
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Count Up Method Subtract by Adding Up
Students make so many errors with this method. The Count Up Method 1000 - 279 = ? 279 +1 = 280 + 20 = 300 +700 = 1000 This uses the concept of “difference.” How far is it from 279 to 1000? 721
Count Up Method Students must understand that with subtraction they know the whole and one of the parts and they must find the other part. When the parts are known, they add back together to be the whole (starting) quantity. Students develop a strong understanding of the relationship between addition and subtraction and often develop this method first using a number line. This is especially useful in counting back money and is sometimes called the cashier’s method.