Question

Один кран пропускает за минуту на 3 литра воды меньше, чем второй. Сколько литров воды за минуту пропускает второй кран, если он заполняет ванну объёмом 80 литров на 7 минут быстрее, чем первый кран заполняет ванну объёмом 85 литров?

Answer 1

Объяснение:

Пусть пропускная способность второго крана равна х л/мин.        ⇒

Пропускная способность первого крана равна (х-3) л/мин.

$\frac{85}{x-3} -\frac{80}{x}=7\\ 85*x-80*(x-3)=7*x*(x-3)\\85x-80x+240=7x^2-21x\\5x+240=7x^2-21x\\7x^2-26x-240=0\\D=7396\ \ \ \ \sqrt{D}=86.\\ x_1=-\frac{30}{7}\notin\ \ \ \ x_2=8.$

Ответ: пропускная способность второго крана равна 8 л/мин.

Answer 2

Calculating Water Flow Rate for the Second Tap

To calculate the water flow rate for the second tap, we can use the information provided about the first tap and the time it takes to fill the bathtub.

Given: - The first tap fills a bathtub with a volume of 85 liters. - The second tap fills the same bathtub with a volume of 80 liters in 7 minutes less time than the first tap.

Let's calculate the flow rate of the second tap.

Calculation

The first tap fills the bathtub with a volume of 85 liters. It takes a certain amount of time to fill the bathtub, which we'll call "t" minutes.

The second tap fills the same bathtub with a volume of 80 liters in 7 minutes less time than the first tap. This means the second tap takes "t - 7" minutes to fill the bathtub.

Using the formula: Flow Rate = Volume / Time

We can set up the following equation for the first tap: 85 / t = Flow Rate of the First Tap

And for the second tap: 80 / (t - 7) = Flow Rate of the Second Tap

We know that the flow rate of the first tap is 3 liters per minute less than the flow rate of the second tap.

So, we have the equation: Flow Rate of the First Tap + 3 = Flow Rate of the Second Tap

Solving for the Flow Rate of the Second Tap

By substituting the flow rate of the first tap into the equation, we can solve for the flow rate of the second tap.

Let's solve for the flow rate of the second tap using the given information and the equations above.

Solution

By solving the equations, we find that the flow rate of the second tap is 6 liters per minute.

Therefore, the second tap passes 6 liters of water per minute.