Two-fifths 2845

David goes to school by bike and says: "If I go 300 meters further than two-fifths of the way to school, I have just walked one kilometer of the way." How far is David from home to school?

Correct answer:

x =  1.75 km

Step-by-step explanation:

$$\begin{gathered} a=300\text{m}\to \text{km}=300:1000\text{km}=0.3\text{km} \\ b=1\text{km} \\ a+\frac{2}{5}\cdot x=b \\ 0.3+\frac{2}{5}\cdot x=1 \\ 0.3+2/5\cdot x=1 \\ 2x=3.5 \\ x=\frac{3.5}{2}=1.75 \\ x=\frac{7}{4}=1.75=1.75\text{km} \end{gathered}$$

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