A woman 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:	Choose one.
A) 71.11 km/hr. B) 68.11 km/hr. C) 44.11 km/hr. D) 88.11 km/hr. E) 31.11 km/hr.
A   71.11 km/hr.   Total time taken = 160/64 + 160/80 = 9/2 hours   --&gt; 71.11 km/hr.verage speed = 320 x 2/9 = 71.11 km/hr.
<result>A</result>
A woman 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: