Company car

Ms. Vaňková has a company car equipped with a multifunction indicator, on which she can monitor the average petrol consumption during individual rides. During the first ride, mostly in city traffic, it traveled 20.5 km, with an average consumption of 7.8L/100km. In the next two trips, mainly outside the city, she drove 115.5 km first, with an average consumption of 6.2L/100 km, and then 130 km with an average consumption of 5.8L/100 km. Calculate the total gasoline consumption for all three rides?

Correct answer:

s =  16.3 l

Step-by-step explanation:

$$\begin{gathered} s_1=7.8\cdot \frac{20.5}{100}=1.599\text{l} \\ {s}_2=6.2\cdot \frac{115.5}{100}=7.161\text{l} \\ {s}_3=5.8\cdot \frac{130}{100}=\frac{377}{50}=7.54\text{l} \\ s=s_1+s_2+s_3=s_1+s_2+\frac{377}{50}=1.599+7.161+7.54=\frac{163}{10}\text{l}=16.3\text{l} \end{gathered}$$

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