A man 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:
35.55 km/hr
36 km/hr
71.11 km/hr
71 km/hr
Explanation:
Total time taken =$ \left(\dfrac{160}{64} +\dfrac{160}{80} \right) $hrs.=$ \dfrac{9}{2} $hrs. |
$\therefore$ Average speed =$ \left(320 \times\dfrac{2}{9} \right) $km/hr= 71.11 km/hr. |