The distance from the dacha to the river is 4.5 km. The first pedestrian left the river towards the dacha at a speed of 4 km / h.

The distance from the dacha to the river is 4.5 km. The first pedestrian left the river towards the dacha at a speed of 4 km / h. After 30 minutes a second pedestrian came out to meet him from the dacha. Find the speed (in km / h) of the second pedestrian if it is known that the meeting of pedestrians occurred at a distance of 3 km from the river

1) Find the distance that the first pedestrian traveled before the meeting. If the meeting of pedestrians occurred 3 km from the river, it means that he walked 3 km.
2) How long did the first pedestrian walk before meeting the second pedestrian? To find time, you need to divide the distance by the speed.
3: 4 = 3/4 = 0.75 (h)
3) How many hours did the second pedestrian travel? He went out for 30 minutes. = 1/2 h = 0.5 h later than the first, which means that he was on the way 0.5 hours less than the first pedestrian.
0.75 – 0.5 = 0.25 (h)
4) How many kilometers did the second pedestrian walk?
4.5 – 3 = 1.5 (km)
5) How fast was the second pedestrian walking? To find speed, you need to divide the distance by the time.
1.5: 0.25 = 6 (km / h)
Answer. 6 km / h.