Question

Теплоход и катер вышли одновременно навстречу друг другу из двух портов, расстояние между которыми 300 км. Средняя скорость движения катера 40 км/ч. Узнай среднюю скорость движения теплохода, если он встретился с катером через 3 ч. Задачу нужно решить разными способами. Придумай свое условие. Из 28 кг сливок получают 10 кг сливочного масла. 1) Сколько килограммов масла получится таким способом из 1680 кг сливок? 2) Сколько килограммов сливок надо взять, чтобы таким способом получить 150 кг сливочного масла? Поезд отправляется в 19 ч 35 мин. Дорога пассажира от дома до вокзала занимает 45 мин. В котором часу пассажиру надо выехать из дома, чтобы быть на вокзале за 15 мин. до отправления поезда?

Answer 1

1)40 *3= 120(км) прошел катер

2) 300 - 120 = 180(км) прошел теплоход

3) 180: 3 = 60 (км/час) скорость теплохода

 

1) 1680:28= 60(р) помещается 28 в 1680

2) 60 * 10 = 600(кг) масла можно получить с 1680 кг сливок.

3) 150:10=15(р)

4) 28*15=420(кг) сливок

Ответ: 420кг нужно сливок, чтобы получить 150 кг масла.

 

1) 45+15 = 60 (мин)

2) 19час45 мин - 60 мин= 18 час 45 мин нужно выйти из дома

Ответ: 18час 45 мин нужно выйти из дома.

 

Answer 2

Problem 1: Speed of the Boat and the Motorboat

To find the average speed of the boat, we can use the formula:

Average Speed = Total Distance / Total Time

Given: - Distance between the ports: 300 km - Speed of the motorboat: 40 km/h - Time taken to meet: 3 hours

Let's calculate the average speed of the boat.

Step 1: Calculate the distance covered by the motorboat in 3 hours. - Distance = Speed × Time - Distance = 40 km/h × 3 hours - Distance = 120 km

Step 2: Calculate the remaining distance between the boat and the motorboat when they meet. - Remaining Distance = Total Distance - Distance covered by the motorboat - Remaining Distance = 300 km - 120 km - Remaining Distance = 180 km

Step 3: Calculate the time taken by the boat to cover the remaining distance. - Time = Distance / Speed - Time = 180 km / Speed

Now, we need to find the speed of the boat. To do this, we need to know the time taken by the boat to cover the remaining distance. Unfortunately, the time taken by the boat is not provided in the question. Could you please provide the time taken by the boat to cover the remaining distance?

Problem 2: Conversion of Cream to Butter

To solve this problem, we need to find the ratio of cream to butter and then use it to calculate the required quantities.

Given: - 28 kg of cream produces 10 kg of butter

Problem 2.1: How much butter can be produced from 1680 kg of cream?

To find the amount of butter produced, we can set up a proportion:

Cream : Butter = 28 kg : 10 kg

Let's solve the proportion:

Step 1: Set up the proportion: - 28 kg / 10 kg = 1680 kg / x

Step 2: Cross-multiply and solve for x: - 28 kg * x = 10 kg * 1680 kg - 28x = 16800 kg - x = 16800 kg / 28 - x = 600 kg

Therefore, 600 kg of butter can be produced from 1680 kg of cream.

Problem 2.2: How much cream is needed to produce 150 kg of butter?

To find the amount of cream needed, we can set up a proportion:

Cream : Butter = 28 kg : 10 kg

Let's solve the proportion:

Step 1: Set up the proportion: - 28 kg / 10 kg = x kg / 150 kg

Step 2: Cross-multiply and solve for x: - 28 kg * 150 kg = 10 kg * x kg - 4200 kg = 10x - x = 4200 kg / 10 - x = 420 kg

Therefore, 420 kg of cream is needed to produce 150 kg of butter.

Problem 3: Departure Time for the Train

To find the departure time for the passenger, we need to subtract the travel time from the desired arrival time.

Given: - Train departure time: 19:35 (7:35 PM) - Travel time from home to the station: 45 minutes - Desired arrival time at the station: 15 minutes before the train departure time

Step 1: Subtract the travel time from the desired arrival time: - Desired arrival time = Train departure time - Travel time - 15 minutes - Desired arrival time = 19:35 - 45 minutes - 15 minutes

Step 2: Perform the subtraction: - Desired arrival time = 19:35 - 1 hour - 15 minutes - Desired arrival time = 18:20 (6:20 PM)

Therefore, the passenger should leave home at 18:20 (6:20 PM) to arrive at the station 15 minutes before the train departure time.

Please let me know if there's anything else I can help you with!