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CEMC Cayley, 2026

Algebra Difficulty 1.5 Junior Find the answer Canada

If 2m−nn=35\dfrac{2m-n}{n} = \dfrac{3}{5}, then the value of mn\dfrac{m}{n} is

Pick one

Solution

Solution 1:

If 2m−nn=35\dfrac{2m-n}{n}=\dfrac35,
then 5(2m−n)=3n5(2m-n)=3n or 10m−5n=3n10m-5n=3n. Simplifying, we get 10m=8n10m=8n and so mn=810=45\dfrac{m}{n}=\dfrac{8}{10}=\dfrac45.

Solution 2:

If 2m−nn=35\dfrac{2m-n}{n}=\dfrac35,
then 2mn−nn=35\dfrac{2m}{n}-\dfrac{n}{n}=\dfrac35 or
2mn−1=35\dfrac{2m}{n}-1=\dfrac35.
Simplifying, we get 2mn=85\dfrac{2m}{n}=\dfrac{8}{5}, and so mn=85×12=45\dfrac{m}{n}=\dfrac{8}{5}\times\dfrac12=\dfrac45.

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