Running Distances of Friends

Three friends, Jana, Jannet, and Adriana, like to run. On Sunday they all went for a run. Jana ran twice as many kilometres as Jannet. Adriana ran 3 kilometres more than Jannet. How many kilometres did Adriana run if the friends ran 11 kilometres in total?

Final Answer:

a =  5 km

Step-by-step explanation:

$$\begin{gathered} j+z+a=11 \\ j=2z \\ a=3+z \\ 2z+z+(3+z)=11 \\ 2\cdot z+z+(3+z)=11 \\ 4z=8 \\ z=\frac{8}{4}=2 \\ z=2 \\ j=2\cdot z=2\cdot 2=4\text{km} \\ a=3+z=3+2=5\text{km} \end{gathered}$$

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