A pedestrian walked for 1 hour at a speed of 4 km / h, and then for another 1 hour he rode a bicycle at a speed of 16 km / h. What is the average speed along the way?
Initial data: t1 (duration of movement of a pedestrian on foot) = 1 hour; V1 (walking speed) = 4 km / h; t2 (duration of cycling) = 1 hour; V2 (cycling speed) = 16 km / h.
Since a pedestrian moved on foot and on a bicycle at equal intervals of time, the general formula for calculating his average speed Vav. = (S1 + S2) / (t1 + t2) will take the form Vav. = (V1 + V2) / 2.
Calculation: Vav. = (4 + 16) / 2 = 10 km / h.
Answer: B) the average speed of a pedestrian along the entire path is 10 km / h.
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