One-third of the straight section of the path the cyclist was moving 36 km / h and two-thirds of 24

One-third of the straight section of the path the cyclist was moving 36 km / h and two-thirds of 24 km / h find the average speed for the entire path

Average speed of a cyclist:
Vav. = S / t, where S is the path covered by the cyclist (S = S1 + S2, where S1 = 1/3 S, S2 = 2/3 S), t is the time of movement (t = t1 + t2).
t1 = S1 / V1, t2 = S2 / V2, where V1 is the speed in the first section (V1 = 36 km / h), V2 is the speed in the second section (V2 = 24 km / h).
Vav. = S / t = S / (S1 / V1 + S2 / V2) = S / (1 / 3S / 36 + 2 / 3S / 24) = 1 / (0.00926 + 0.02778) = 1 / 0.037 = 27 km / h.
Answer: The average speed of a cyclist is 27 km / h.