Question

Марк бежал в магазин со скоростью 15 км/ч и прибыл за 10 мин до закрытия . Если бы он бежал на 3 км/ч медленнее,то опоздал бы на 5 мин.Сколько километров пробежал Марк?

Answer 1

X/15 -время Миши.
x/15+1/6 время до поезда
15-3=12 
x/12-1/12 время до поезда

x/12-1/12=x/15+1/6
x/60=1/4  x=15 

Answer 2

Problem Analysis

We are given that Mark ran to a store at a speed of 15 km/h and arrived 10 minutes before closing time. If he had run 3 km/h slower, he would have been 5 minutes late. We need to determine the distance Mark ran.

Solution

Let's assume the distance Mark ran is d kilometers.

We can use the formula speed = distance / time to create two equations based on the given information.

Equation 1: Mark's speed when he arrived early 15 km/h = d km / (time taken to reach the store)

Equation 2: Mark's speed when he would have been late (15 - 3) km/h = d km / (time taken to reach the store + 5 minutes)

We know that time is equal to distance divided by speed. So, we can rewrite the equations as follows:

Equation 1: 15 km/h = d km / (time taken to reach the store)

Equation 2: 12 km/h = d km / (time taken to reach the