Answer: Yochanan covered 5km by walking and 30 km by travelling on the bus.
Step-by-step explanation:
Let x represent the distance that Yochanan covered by walking.
Time = distance/speed
Yochanan walked from home to the bus stop at an average speed of 5km/h. This means that the time it took him to travel x km would be
x/5
The distance from his home to school is 35 kilometers. This means that the distance that he covered while travelling on the bus is 35 - x
He immediately got on his school bus and traveled at an average speed of 60km/h until he got to school. It means that the time that it took him to travel (35 - x) km would be
(35 - x)/60
If the entire trip took 1.5 hours, it means that
x/5 + (35 - x)/60 = 1.5
Cross multiplying by 60, it becomes
12x + 35 - x = 90
12x - x = 90 - 35
11x = 55
x = 55/11 = 5
The distance covered while travelling on the bus is
35 - 5 = 30km