Question

Две трубы , работая вместе , могут наполнить бассейн за 15 мин . Если бы первая труба работала одна , то наполнение бассейна заняло бы 20 мин.Сколько времени понадобится для заполнения бассейна через вторую трубу??(По действиям))

Answer 1

1:15=1/15 часть заполняют две трубы вместе за 1 мин
1:20=1/20 часть заполняет первая труба за 1 мин
1/15-1/20=1/60 часть заполняет вторая труба за 1 мин
1:1/60=60 мин=1 час нужно второй трубе
Ответ 1 час понадобится второй трубе

Answer 2

Весь бассейн - 1 часть.
1) 1 : 15 = 1/15 часть - наполняют обе трубы за 1 минуту.
2) 1 : 20 = 1/20 часть - наполняет за 1 минуту первая труба
3) 1/15 - 1/20 = 1/60 часть - наполняет вторая труба за 1 минуту
4) 1 : 1/60 = 60 минут  - наполняет вторая труба одна весь бассейн

Answer 3

Problem Analysis

We are given that two pipes can fill a swimming pool together in 15 minutes. If the first pipe were to work alone, it would take 20 minutes to fill the pool. We need to determine how long it would take for the second pipe to fill the pool on its own.

Solution

Let's assume that the first pipe can fill 1/20th of the pool in 1 minute, and the second pipe can fill 1/xth of the pool in 1 minute.

According to the given information, when both pipes work together, they can fill the pool in 15 minutes. This means that in 1 minute, they can fill 1/15th of the pool. Therefore, the combined rate of the two pipes is 1/15th of the pool per minute.

We can set up the following equation to represent the combined rate of the two pipes: 1/20 + 1/x = 1/15

To solve for x, we can multiply both sides of the equation by 60x to eliminate the fractions: 3x + 60 = 4x

Simplifying the equation, we find: x = 60

Therefore, the second pipe can fill the pool on its own in 60 minutes.

Answer

The second pipe will take 60 minutes to fill the pool on its own.

Explanation

When both pipes work together, they can fill the pool in 15 minutes. If the first pipe were to work alone, it would take 20 minutes to fill the pool. By solving the equation 1/20 + 1/x = 1/15, we find that the second pipe can fill the pool on its own in 60 minutes