Pennies

Eight hundred pennies have the same value as 100 ducats. One hundred pennies have the same value as 250 tolars. How many ducats have the same value as 100 tolars?

Final Answer:

x =  5

Step-by-step explanation:

$$\begin{gathered} r=\frac{100}{250}\cdot \frac{100}{800}=\frac{100\cdot 100}{250\cdot 800}=\frac{10000}{200000}=\frac{1}{20}=0.05 \\ x=100\cdot r=100\cdot \frac{1}{20}=\frac{100\cdot 1}{20}=\frac{100}{20}=5 \end{gathered}$$

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