A person purchases some article at the rate of rupees 5 per 4 articles and sells them at the rate of rupees 4 per 5 articles. Find the total profit or loss in %.

36 % loss

CP₄ = Rs 5 

SP₅ = Rs 4  

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CP_4x5 = Rs 5 x 5

SP_5x4 = Rs 4 x 4

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CP₂₀ = Rs 25

SP₂₀ = Rs 16

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As CP is more than SP, thus, there is a loss.

Loss% =  \(\frac{CP_{20}-SP_{20}}{CP_{20}}\) * 100

Loss% =  \(\frac{\text{25-16}}{25}\) * 100

Loss% = \(\frac{9 }{25 }\) * 100

Loss% = 36%