The distance between points A and B is 435 km. At the same time, two cars left these points towards each other

The distance between points A and B is 435 km. At the same time, two cars left these points towards each other and met after 3 hours. Find the speed of each car if the speed of one of them is 5 km / h less than the speed of the other. Two buses simultaneously and in opposite directions left the villages, the distance between which is 30 km The first bus was traveling at a speed of 60 km / h, and the second at a speed 10 km / h higher than the first bus. At what distance will the buses be from each other 3 hours after the departure? The boat runs along the river between two cities, the distance between which is 63 km. The boat’s own speed is 15 km / h, and the current speed is 6 km / h. How long will the boat take for one round trip?

1) A – vehicle speed.
3 * (A + A – 5) = 435;
6 * A – 15 = 435;
6 * A = 435 + 15;
A = 450/6;
A = 75;
75 – 5 = 70 km / h speed of the second car.
Answer: 75 and 70 kilometers per hour.
2) 60 + 10 = 70 kilometers per hour the speed of the second bus.
70 + 60 = 130 km / h – approach speed.
130 * 3 = 390 km – will be covered in 3 hours.
390 – 30 = 360 km is the distance between them.
Answer: 360 km.
3) 63 / (6 + 15) = 3 hours – with a passing stream
63 / (15 – 6) = 7 hours – upstream.
3 + 7 = 10 hours – total.
Answer: the boat will take 10 hours.