Maths Olympiad Prep

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, 2026

Algebra Difficulty 1.0 Junior Find the answer Canada

The value of 87+65+43+218-7+6-5+4-3+2-1
is

Pick one

Solution

Since 87=65=43=21=18-7=6-5=4-3=2-1=1,
then (87)+(65)+(43)+(21)=1+1+1+1=4(8-7)+(6-5)+(4-3)+(2-1)=1+1+1+1=4.

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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.