Question

В цистерне было 4800 л воды.Один насос может выкачать всю воду за 24 мин, а второй- за 40 мин.За сколько минут можно выкачать всю воду, если включить сразу два насоса ?

Answer 1

Скорость первого насоса 4800 л/24мин=200л/мин

Скорость второго насова 4800 л/40 мин=120л/мин

200+120=320 Столько они выкачают вместе за минуту

4800/320=15мин ответ

Answer 2

V первого насоса = 4800 л: 24мин=200л/мин

V второго насова 4800 л: 40 мин=120л/мин

200+120=320 - это то, сколько они вместе выкачивают за минуту =>

4800: 320=15(мин)

Ответ: Всю воду оба насоса выкачают за 15 минут.

V- скорость

Answer 3

Problem Analysis

We are given that there is 4800 liters of water in a tank. One pump can pump out all the water in 24 minutes, and another pump can pump out all the water in 40 minutes. We need to determine how long it will take to pump out all the water if both pumps are turned on simultaneously.

Solution

To solve this problem, we can calculate the rate at which each pump can pump out water per minute. Then, we can add the rates of both pumps to find the combined rate at which they can pump out water. Finally, we can divide the total amount of water (4800 liters) by the combined rate to find the time it takes to pump out all the water.

Let's calculate the rates of each pump first:

- Pump 1: It can pump out all the water in 24 minutes. Therefore, its rate is 4800 liters / 24 minutes = 200 liters per minute. - Pump 2: It can pump out all the water in 40 minutes. Therefore, its rate is 4800 liters / 40 minutes = 120 liters per minute.

Now, let's calculate the combined rate of both pumps:

- Combined rate = Rate of Pump 1 + Rate of Pump 2 = 200 liters per minute + 120 liters per minute = 320 liters per minute.

Finally, let's calculate the time it takes to pump out all the water using the combined rate:

- Time = Total amount of water / Combined rate = 4800 liters / 320 liters per minute = 15 minutes.

Therefore, it will take 15 minutes to pump out all the water if both pumps are turned on simultaneously.

Answer

If both pumps are turned on simultaneously, it will take 15 minutes to pump out all the water from the tank.