A man 21

A man sells a bicycle at a profit of 25%. Had he bought it at a price less by 25% and sold it at 250 euro less than also he could have made a profit of 25%. Find cost price.

Final Answer:

a =  800 eur

Step-by-step explanation:

$$\begin{gathered} r=100\%+25\%=1+\frac{25}{100}=1.25 \\ m=100\%-25\%=1-\frac{25}{100}=0.75 \\ a\cdot r=b \\ a\cdot m\cdot r=b-250 \\ a\cdot m\cdot r=a\cdot r-250 \\ 250=a\cdot r-a\cdot m\cdot r \\ a=\frac{250}{r-m\cdot r}=\frac{250}{1.25-0.75\cdot 1.25}=800\text{eur} \end{gathered}$$

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