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UKMT Senior Mathematical Challenge, 2019

Geometry Difficulty 3.0 AMC 10/12 Find the answer United Kingdom

In a square garden $PQRT$ of side $10$ m, a ladybird sets off from $Q$ and moves along edge $QR$ at $30$ cm per minute. At the same time, a spider sets off from $R$ and moves along edge $RT$ at $40$ cm per minute. What will be the shortest distance between them, in metres?

(A) $5$ (B) $6$ (C) $5\sqrt{2}$ (D) $8$ (E) $10$

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