RATL 1 | Lesson 1 | Making Connections Solutions

  1. Show the addition using number lines and a more traditional approach for the following:

\(\dfrac{4}{5} +\dfrac{1}{2}\)

\(\dfrac{4}{5} +\dfrac{1}{2}\)

Lowest Common Denominator (LCD) of 5 and 2 is the product of the two or 10

\(\dfrac{2}{2}•\dfrac{4}{5} + \dfrac{5}{5}•\dfrac{1}{2}\)

\(\dfrac{8}{10} +\dfrac{5}{10} = \dfrac{13}{10}\)

  1. Explain how the representations created by these strategies are related to each other.

On the number line, note that in the first addend you have 5 divisions and 2 divisions in the second addend. In order to add equal parts, you need to divide the fifths in half resulting in dividing into tenths which is the LCD.  Before adding on the number line or algorithmically, the LCD is noted first.

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