PRE-ALGEBRALesson 95 of 171
Students learn to solve proportions using cross products. For example, to solve the proportion 9/15 = 6/d, remember that the cross products of a proportion must be equal, so 9 x d = 15 x 6, or 9d = 90, and dividing both sides by 9, d = 10.
Elementary / Middle
High School Math
*Also referred to as Elementary Algebra or Beginning Algebra.
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