The car travels the path at different speeds, the first section at a speed of 60 km per hour in 30 minutes

The car travels the path at different speeds, the first section at a speed of 60 km per hour in 30 minutes, the second section at 100 km per hour in 1 hour, the third section at a speed of 80 km per hour in 30 minutes. determine the average speed.

Task data: first section (V1 = 60 km / h; t1 = 30 min (0.5 h)); second section (V2 = 100 km / h; t2 = 1 h); third section (V3 = 80 km / h; t3 = 30 min (0.5 h)).
The average speed of the machine is calculated by the formula: Vav. = S / t = (S1 + S2 + S3) / (t1 + t2 + t3) = (V1 * t1 + V2 * t2 + V3 * t3) / (t1 + t2 + t3).
Calculation: Vav. = (60 * 0.5 + 100 * 1 + 80 * 0.5) / (0.5 + 1 + 0.5) = 170/2 = 85 km / h.
Answer: The car traveled at an average speed of 85 km / h.