Question:
Adom's on tour travels first 160 km at 64 km/hr and the next 160 km at 80 km/hr. The average speed for the first 320 km of the tour is?
A71.11km/hr
B68km/hr
C73.4km/hr
D65km/hr
Answer:
A. 71.11km/hr
Explanation:
X=64 y=80 Average speed 2xy/(x+y)= (2x61x80)/ (64+80) = (2 × 64 × 80)/144 =71.11 km/hr