The road between points A and B consists of an ascent and a descent and its length is 40 km.

The road between points A and B consists of an ascent and a descent and its length is 40 km. The tourist covered the path A and B in 8 hours of which the descent took 4 hours at what speed the tourist was going downhill if his speed uphill is less than the speed on the descent on 2 km / h.

Downhill speed – x, then uphill speed – (x – 2).
S = V * t – the formula for finding the distance.
S1 = 4 * x;
S2 = 4 * (x – 2);
4 * (x – 2) + 4x = 40;
4x – 8 + 4x = 40;
8x = 48;
x = 6 (km / h) – the speed of the tourist on the descent.
Answer: the speed of the tourist on the descent is 6 km / h.