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PRE-ALGEBRALesson 4 of 171

ADDITION AND SUBTRACTION

Addition

Students learn to add numbers with two or more digits, such as 139 + 25. The first step is to line up the numbers vertically so that the units digits are in the same column. Next, add the units digits, the tens digits, and the hundreds digits. Adding the units digits, 9 + 5 = 14, which more...

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*Also referred to as Elementary Algebra or Beginning Algebra.

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