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A large disc of radius 25 cm has a smaller disc of… | StemPy Lab

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A large disc of radius 25 cm has a smaller disc of radius 20 cm stuck at its middle. A straight scratch across the large disc just touches the small disc. How long is the scratch?

MathematicsHardHigh School (9–10)GeneralGeometry › Circles Board Exam SAT

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A large disc of radius $25\ \text{cm}$ has a smaller disc of radius $20\ \text{cm}$ stuck at its middle. A straight scratch across the large disc just touches the small disc. How long is the scratch?

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