The body traveled 0.3 ways at a speed of 54 km / h, and the rest of the way at a speed of 36 km / h.

The body traveled 0.3 ways at a speed of 54 km / h, and the rest of the way at a speed of 36 km / h. Find the average speed?

To find the average ground speed of the body in question, we will use the formula: Vav = S / t = S / (t1 + t2) = S / (0.3S / V1 + 0.7S / V2) = 1 / (0.3 / V1 + 0.7 / V2).

Variables: V1 – speed on the first (0.3) part of the track (V1 = 54 km / h); V2 – speed on the remaining (0.7) part of the path (V2 = 36 km / h).

Let’s calculate: Vav = 1 / (0.3 / V1 + 0.7 / V2) = 1 / (0.3 / 54 + 0.7 / 36) = 1 / 0.025 = 40 km / h.

Answer: The average ground speed of the body in question was 40 km / h.