Question

два автомобиля выехали в разное время в одном направлении и едут со скоростью 75 км/ч и 90 км/ч. Первый автомобиль выехал на 2 ч раньше. Догонит ли второй автомобиль первый? Через какое время? На каком расстоянии от начала пути?

Answer 1

1) 75*2=150 км - проехал первый автомобиль до выезда второго автомобиля

2) 90-75=15 км\час - разница скоростей автомоблией (на столько км в час сокращается расстояние между автомоблиями)

3) 150:15=10 час - через столько времени второй автомобиль догонит первый

4) 90*10=900 км - на таком расстоянии от начала пути второй автомоблиь догонит первый

ответ: через 10 часов догонит на расстоянии 900 км от начала пути

Answer 2

Problem Analysis

We have two cars traveling in the same direction. The first car is traveling at a speed of 75 km/h, while the second car is traveling at a speed of 90 km/h. The first car started 2 hours earlier than the second car. We need to determine if the second car will catch up to the first car, and if so, after how much time and at what distance from the starting point.

Solution

To solve this problem, we can use the formula: distance = speed x time.

Let's assume that the second car catches up to the first car after time 't'.

The distance traveled by the first car in 't' hours is given by: distance1 = 75t.

The distance traveled by the second car in 't' hours is given by: distance2 = 90(t-2). (Note: The second car started 2 hours later than the first car, so we subtract 2 from 't'.)

To find the time at which the second car catches up to the first car, we can set the distances equal to each other and solve for 't':

75t = 90(t-2).

Simplifying the equation, we get:

75t = 90t - 180.

Solving for 't', we find:

t = 12.

So, the second car will catch up to the first car after 12 hours.

To find the distance from the starting point at which the second car catches up to the first car, we can substitute the value of 't' into either of the distance formulas. Let's use the formula for the distance traveled by the first car:

distance1 = 75t.

Substituting 't = 12', we get:

distance1 = 75 * 12 = 900 km.

Therefore, the second car will catch up to the first car after 12 hours, and it will be at a distance of 900 km from the starting point.

Answer

The second car will catch up to the first car after 12 hours. At that time, the second car will be at a distance of 900 km from the starting point.