Cyclist race fraction

During the race, the cyclists covered 3/7 of the total length and had 80.5 km to go. How long was the race, and what part of the race did they complete at 55 km? An example of calculating in fractions.

Final Answer:

x =  140.875 km
b =  440/1127

Step-by-step explanation:

$$\begin{gathered} x-\frac{3}{7}\cdot x=80.5 \\ x-3/7\cdot x=80.5 \\ 4x=563.5 \\ x=\frac{563.5}{4}=140.875 \\ x=\frac{1127}{8}=140.875=\frac{1127}{8}\text{km}=140.875\text{km} \end{gathered}$$

$b=\frac{55}{x}=\frac{55}{140.875}=\frac{440}{1127}=0.3904$

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