Question

Грузовик выехал из села А в 10 часов. Через 15 минут из того же села в противоположном направлении выехал мотоциклист, скорость которого была на 20% меньше скорости грузовика. Чему равны скорости грузовика и мотоциклиста, если в 11 часов расстояние между ними составило 96 км?

Answer 1

S=0,25V1+(V1+V2)*0,75
V2=0,8*V1
S=1,6*V1
V1=5*S/8=60 км/ч
V2=0,8*60=48 км/ч

Answer 2

Problem Analysis

We are given that a truck left village A at 10:00 AM, and 15 minutes later, a motorcyclist left the same village in the opposite direction. The motorcyclist's speed was 20% less than the speed of the truck. We need to find the speeds of the truck and the motorcyclist if the distance between them at 11:00 AM was 96 km.

Solution

Let's assume the speed of the truck is x km/h. Since the motorcyclist's speed is 20% less than the truck's speed, the motorcyclist's speed is 0.8x km/h.

We know that the distance traveled by an object is equal to its speed multiplied by the time taken.

From 10:00 AM to 11:00 AM, the truck traveled for 1 hour, and the motorcyclist traveled for 45 minutes (15 minutes less than 1 hour).

Using the distance formula, we can set up the following equation:

Distance traveled by the truck = Distance traveled by the motorcyclist + 96 km

x km/h * 1 hour = 0.8x km/h * (45/60) hours + 96 km

Simplifying the equation:

x = 0.8x * (3/4) + 96

x = (3/4) * 0.8x + 96

x = 0.6x + 96

0.4x = 96

x = 240

Therefore, the speed of the truck is 240 km/h and the speed of the motorcyclist is 0.8 * 240 = 192 km/h.

Answer

The speed of the truck is 240 km/h and the speed of the motorcyclist is 192 km/h.