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UKMT Grey Kangaroo, 2022

Algebra Difficulty 2.0 Junior Find the answer United Kingdom

The villages $P$ , $Q$ , $R$ and $S$ are situated, not necessarily in that order, on a long straight road. The distance from $P$ to $R$ is 75 km, the distance from $Q$ to $S$ is 45 km and the distance from $Q$ to $R$ is 20 km. Which of the following could not be the distance, in km, from $P$ to $S$ ?

(A) $10$ (B) $50$ (C) $80$ (D) $100$ (E) $140$

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