Question

Водителю легковой машины надо попасть из Зареченска в Ивантеевку не позже 7 часов вечера того же дня.Во сколько ему надо встать в день выезда,если на всё дела перед отъездом ему необходимо 90 минут,по дороге он собирается сделать получасовую остановку на заправочной станции,а ехать будет со скоростью 80 км/ ч?Помогите решить,расстояние между Зареченска и Ивантеевки 800 км

Answer 1

1) 800/80=10 часов составит путь
2) 10ч+90мин=11ч 30мин это вместе с делами)
3) 11ч 30 мин+ 30 мин= 12 час это время пути с остановкой на заправку
4) соответственно ему надо выехать не позже 7 часов утра, что бы быть в Ивантеевке не позднее 7 вечера.

Answer 2

Calculation of Departure Time

To calculate the departure time for the driver, we need to consider the time required for pre-departure tasks, the duration of the journey, and any planned stops along the way.

Given the following information: - The driver needs to arrive in Ivan'teevka no later than 7:00 PM on the same day. - The driver requires 90 minutes for pre-departure tasks. - The driver plans to make a 30-minute stop at a gas station. - The distance between Zarechensk and Ivan'teevka is 800 km. - The driver intends to travel at a speed of 80 km/h.

Let's calculate the total time required for the journey and work backward to determine the departure time.

Time Calculation

1. Time required for the journey: - Distance: 800 km - Speed: 80 km/h - Time = Distance / Speed = 800 km / 80 km/h = 10 hours

2. Time required for pre-departure tasks: 90 minutes

3. Planned stop at a gas station: 30 minutes

4. Total time required for the journey: - Time for the journey: 10 hours - Pre-departure tasks: 90 minutes - Gas station stop: 30 minutes - Total time = Time for the journey + Pre-departure tasks + Gas station stop = 10 hours + 90 minutes + 30 minutes

To determine the departure time, we subtract the total time required for the journey from the desired arrival time:

7:00 PM - (10 hours + 90 minutes + 30 minutes)

Calculation

1. Convert the desired arrival time to minutes: - 7:00 PM = 7 * 60 minutes + 0 minutes = 420 minutes

2. Calculate the total time required for the journey in minutes: - Total time = 10 hours * 60 minutes/hour + 90 minutes + 30 minutes

3. Subtract the total time from the desired arrival time: - Departure time = Desired arrival time - Total time

Departure Time Calculation

Departure time = 420 minutes - (10 hours * 60 minutes/hour + 90 minutes + 30 minutes)

Now, let's calculate the departure time.

Departure time = 420 minutes - (600 minutes + 90 minutes + 30 minutes)

Departure time = 420 minutes - 720 minutes

Departure time = -300 minutes

The calculated departure time is -300 minutes, which is not a valid time. This suggests that the driver cannot reach Ivan'teevka by 7:00 PM on the same day, given the specified conditions.

To arrive in Ivan'teevka by 7:00 PM, the driver would need to adjust their departure time or consider alternative options, such as increasing their speed or reducing the time spent on pre-departure tasks or at the gas station.

Please note that the calculation assumes a constant speed throughout the journey and does not account for factors such as traffic, road conditions, or breaks during the journey.