A car travels at 30 m/s for 4 s, then at 40 m/s for 6 s. What is the average speed for the entire trip?
A35 m/s
B36 m/s
C70 m/s
D10 m/s
Explanation
📌 Total distance = (30)(4) + (40)(6) = 120 + 240 = 360 m. Total time = 10 s. Average speed = 360/10 = 36 m/s. Distractor A takes simple average of speeds (35 = (30+40)/2) — wrong because time weights matter; C sums speeds; D uses difference.