Ravi drove for 4 hours at a speed of 70 miles per hour and for 2 hours at 40 miles per hour. What was his average speed (in miles per hour) for the whole journey ?

60

We know ,

Distance = Speed × Time

D1= 4 ×  70 = 280 miles

D2 = 2 × 40 = 80 miles

Total distance = 280 + 80 = 360 miles

Total Time = 4 + 2 = 6 hours

Average Speed = \(\frac{360}{6}\)

= 60 miles/hour