Grade
3

Mobile Math: Missing Pieces

Look at the mobile below. What do you notice? What do you wonder?
Find the missing values so that the mobile is balanced.

The mobile has 2 strings, is balanced, and has a total value of 120. The left side has 4 orange triangles. The right side has 1 purple pentagon and 2 red squares. The pentagon has a value of 12. The other shape values are unknown.

If the value of the pentagon became 28, how could you change the value of the other shapes so that the mobile was still balanced?

The mobile has 2 strings, is balanced, and has a total value of 120. The left side has 4 orange triangles. The right side has 1 purple pentagon and 2 red squares. The pentagon has a value of 28. The other shape values are unknown.

If the total value of the mobile was changed to 200, how could you change the values of the shapes so that the mobile remained balanced? 

The mobile has 2 strings, is balanced, and has a total value of 200. The left side has 4 orange triangles. The right side has 1 purple pentagon and 2 red squares. The shape values are unknown.
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Reference for Educators

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