Use properties of operations to generate equivalent expressions.
Understand that rewriting an expression in different forms in a problem context can shed light on the problem and how the quantities in it are related. For example, a + 0.05a = 1.05a means that “increase by 5%” is the same as “multiply by 1.05.” (7.EE.2) [Also see A.SSE.2, A.SSE.3, A.SSE.3a, A.CED.4]
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