Maths Olympiad Prep

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, 2013

Geometry Difficulty 2.2 Junior Find the answer Canada

In the diagram, rectangle PQRSPQRS has PQ=30PQ=30 and rectangle WXYZWXYZ has ZY=15ZY=15.


If SS is on WXWX and XX is on SRSR so that SX=10SX=10, then WRWR equals

Pick one

Solution

Since PQRSPQRS and WXYZWXYZ are rectangles, then SR=PQ=30SR = PQ=30 and WX=ZY=15WX = ZY = 15.

Since SX=10SX=10, then WS=WXSX=1510=5WS = WX-SX=15-10=5.

Thus, WR=WS+SR=5+30=35WR = WS+SR=5+30=35.

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Source: CEMC, University of Waterloo, licensed CC-BY-NC-4.0. Statement reproduced verbatim; metadata (topic, difficulty) added by this project.