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Try This Geometry Problem

Geometry Level 1

Mary drew a triangle on the board. What is the sum of all interior angles in a triangle?

\[ 90^ \circ \] \[ 180 ^ \circ \] \[ 270 ^ \circ \] \[ 360 ^ \circ \]

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Excel in math and science

Master concepts by solving fun, challenging problems.

It's hard to learn from lectures and videos

Learn more effectively through short, interactive explorations.

Used and loved by over 6 million people

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including olympiad champions, researchers, and professionals.

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by Calvin Lin

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