Question

Помогите пожалуйста решить задачу с помощью уравнения.Первый участок пути мотоциклист ехал со скоростью 42 км/ч, а второй участок-со скоростью 30 км/ч.Всего он проехал 129 км/ч.За сколько времени мотоциклист проехал первый участок пути,и за сколько второй,если на первый участок он затрартил на 0,5 ч меньше чем на второй участок?

Answer 1

Х час - время в пути на ІІ участке
(х-0,5)час - время в пути на І участке
42(х-0,5)+30х=129
42х-21+30х=129
72х=150
х=150:72
х=2 ¹/₁₂ = 2час 05мин - проехал ІІ участок
2ч 05мин - 30мин=1ч 35мин - проехал І участок

Answer 2

Problem Analysis

We are given that a motorcyclist traveled two segments of a path at different speeds. The first segment was covered at a speed of 42 km/h, and the second segment was covered at a speed of 30 km/h. The total distance covered by the motorcyclist is 129 km. We need to find the time taken for each segment, given that the motorcyclist spent 0.5 hours less on the first segment than on the second segment.

Solution

Let's assume that the time taken for the first segment is t hours. Since the motorcyclist spent 0.5 hours less on the first segment than on the second segment, the time taken for the second segment would be t + 0.5 hours.

We can use the formula distance = speed × time to calculate the distance covered in each segment.

For the first segment: - Distance = 42 km/h × t hours

For the second segment: - Distance = 30 km/h × (t + 0.5) hours

Since the total distance covered is 129 km, we can set up the equation:

42t + 30(t + 0.5) = 129

Now, let's solve this equation to find the values of t and t + 0.5.

Calculation

42t + 30(t + 0.5) = 129

Simplifying the equation:

42t + 30t + 15 = 129

72t + 15 = 129

72t = 129 - 15

72t = 114

t = 114 / 72

t ≈ 1.583

Now, we can calculate the time taken for the second segment:

t + 0.5 ≈ 1.583 + 0.5 ≈ 2.083

Answer

The motorcyclist took approximately 1.583 hours for the first segment and approximately 2.083 hours for the second segment.

Please note that these values are approximate due to rounding.

Let me know if you need any further assistance!