Fabric cost calculation

Mom bought the boys the same fabric for their clothes. Pepik has 2.5m of fabric, Karl 1.25m, and Luis 0.3m more than Karl. How many crowns will they pay for fabric if 10 cm costs CZK 13.80?

Final Answer:

x =  648.6

Step-by-step explanation:

$$\begin{gathered} a=2.5\text{m}\to \text{cm}=2.5\cdot 100\text{cm}=250\text{cm} \\ b=1.25\text{m}\to \text{cm}=1.25\cdot 100\text{cm}=125\text{cm} \\ {c}_1=0.30\text{m}\to \text{cm}=0.30\cdot 100\text{cm}=30\text{cm} \\ c=b-c_1=125-30=95\text{cm} \\ {x}_1=13.80/10=\frac{69}{50}=1\frac{19}{50}=1.38\text{Kc/cm} \\ x=x_1\cdot (a+b+c)=1.38\cdot (250+125+95)=648.6 \end{gathered}$$

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