Grandfather 9001

Grandfather left the house on his bicycle at 1 p.m. He drove to the pond and returned home at 3:20 p.m. There and back, he rode the same road across the plain. He stayed at the pond for 1 hour. How many minutes did it take him to get to the pond?

Correct answer:

t₁ =  40 min

Step-by-step explanation:

$$\begin{gathered} t=(15+20/60)-13.00-1.00=\frac{4}{3}\doteq 1.3333\text{h} \\ {t}_1=60\cdot \frac{t}{2}=60\cdot \frac{\frac{4}{3}}{2}=40\text{min} \end{gathered}$$

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