Martha

Martha likes to walk in the park, which is square, 7/10 mi on each side. One morning, Martha walked around the entire park 3 1/2 times before stopping to rest. How far had she walked?

Correct answer:

x =  9 ⁴⁄₅ = 49/5 mi

Step-by-step explanation:

$$\begin{gathered} a=7/10=\frac{7}{10}=0.7\text{mi} \\ o=4\cdot a=4\cdot \frac{7}{10}=\frac{4\cdot 7}{10}=\frac{28}{10}=\frac{14}{5}=2.8\text{mi} \\ k=3\frac{1}{2}=3+\frac{1}{2}=\frac{3\cdot 2+1}{2}=\frac{6+1}{2}=\frac{7}{2}=3.5 \\ x=k\cdot o=\frac{7}{2}\cdot \frac{14}{5}=\frac{7\cdot 14}{2\cdot 5}=\frac{98}{10}=\frac{49}{5}\text{mi}=9\frac{4}{5}\text{mi}=9.8\text{mi} \end{gathered}$$

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