Correct Answer - Option 4 : 42 km/hr
Solution:
Formula Used:
Average speed = Total distance travelled/Total time
Calculations:
Speed (from Delhi to Agra) = 60 Km/hr
Speed (from Agra to Chandigarh) = 60 – 50% of 60 Km/hr
⇒ 30 km/hr
Distance from Delhi to Agra = speed × time
⇒ 60 × 2 = 120 km
Distance from Agra to Chandigarh = speed × time
⇒ 30 × 3 = 90 km
Total Distance = 120 + 90 = 210 km
Total Time = 2 + 3 = 5 hr
Average speed = 210/5 = 42 Km/hr
Hence the average speed from Delhi to Chandigarh is 42 Km/hr.