Question

9. Болельщик хочет успеть на стадион к началу матча. Если он пойдет из дома пешком со скоростью 4 км/ч, то опоздает на 15 мин., а если поедет на велосипеде со скоростью 16 км/ч, то приедет на полчаса раньше. На каком расстоянии от дома находится стадион.

Answer 1

S/4 = t+1/4
S/16=t-1/2
S/16= S/4-1/4-1/2
S=4 км

Answer 2

15+4=19 19-16=3км стадион находится

Answer 3

Problem Analysis

A fan wants to arrive at the stadium before the start of the match. If they walk at a speed of 4 km/h, they will be 15 minutes late. However, if they ride a bicycle at a speed of 16 km/h, they will arrive 30 minutes early. We need to determine the distance from the fan's home to the stadium.

Solution

Let's assume the distance from the fan's home to the stadium is d kilometers.

If the fan walks at a speed of 4 km/h, the time taken to reach the stadium is given by: Time taken = Distance / Speed = d / 4.

According to the problem, if the fan walks, they will be 15 minutes late. We can convert this to hours by dividing 15 minutes by 60: 15 minutes = 15 / 60 = 0.25 hours.

So, the time taken to reach the stadium by walking is: Time taken = d / 4 = d * 0.25.

If the fan rides a bicycle at a speed of 16 km/h, the time taken to reach the stadium is given by: Time taken = Distance / Speed = d / 16.

According to the problem, if the fan rides a bicycle, they will arrive 30 minutes early. We can convert this to hours by dividing 30 minutes by 60: 30 minutes = 30 / 60 = 0.5 hours.

So, the time taken to reach the stadium by riding a bicycle is: Time taken = d / 16 = d * 0.5.

Now, we can set up the following equation based on the given information: Time taken by walking - Time taken by riding a bicycle = 0.25 - 0.5.

Simplifying the equation, we get: d * 0.25 - d * 0.5 = -0.25.

Solving for d, we find: d * 0.25 - d * 0.5 = -0.25, d * (-0.25) = -0.25, d = -0.25 / (-0.25) = 1.

Therefore, the distance from the fan's home to the stadium is 1 kilometer.

Answer

The stadium is located at a distance of 1 kilometer from the fan's home.