###### Alissa Fong

MA, Stanford University
Teaching in the San Francisco Bay Area

Alissa is currently a teacher in the San Francisco Bay Area and Brightstorm users love her clear, concise explanations of tough concepts

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# Adding and Subtracting - Concept

Alissa Fong
###### Alissa Fong

MA, Stanford University
Teaching in the San Francisco Bay Area

Alissa is currently a teacher in the San Francisco Bay Area and Brightstorm users love her clear, concise explanations of tough concepts

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The "whole numbers" are like the numbers we use to count: 0, 1, 2, 3, ... We represent the order of these numbers on a number line, where the smaller numbers are on the left and they get larger as we move right. To add, we move right on the number line to represent numbers getting larger. To subtract, we move left on the number line to represent numbers getting smaller. You already know how to do a lot of this in your head, like when working with earning or spending money, but we put it on a number line to make it more abstract, or general.

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