alleryA car covers the first half of its journey at 60 km/h and the second half at 40 km/h. The AVERAGE speed for the whole journey is:
A48 km/h
B100 km/h
C50 km/h
D45 km/h
Answer & Solution
Correct answer: A. 48 km/h
**Tricky:** average speed ≠ simple average of two speeds when distances are equal.
**Use harmonic mean:** avg = 2×60×40 / (60+40) = 4800/100 = 48 km/h.
(Quick reason: more TIME is spent at the slower speed, so it pulls the average down.)
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