Question

Через одну трубу бассейн можно наполнить водой за 9ч,а через другую-за 11ч. Обе трубы были открыты 1 ч. Какая часть бассейна осталась незаполненной?

Answer 1

1-1/9-1/11=99/99-11/99-9/99=79/99,возможно так

Answer 2

Problem Analysis

We are given two pipes that can fill a swimming pool with water in 9 hours and 11 hours, respectively. Both pipes were opened for 1 hour. We need to determine the fraction of the pool that remains unfilled.

Solution

To solve this problem, we can calculate the rate at which each pipe fills the pool and then determine the fraction of the pool that remains unfilled after 1 hour.

Let's assume that the capacity of the pool is 1 unit (this is an arbitrary assumption since the problem does not provide the actual capacity of the pool). We can then calculate the rate at which each pipe fills the pool by dividing the capacity of the pool by the time it takes for each pipe to fill the pool.

Let's denote the rate at which the first pipe fills the pool as R1 and the rate at which the second pipe fills the pool as R2.

The rate at which the first pipe fills the pool is given by: R1 = 1/9 (since it takes 9 hours to fill the pool)

The rate at which the second pipe fills the pool is given by: R2 = 1/11 (since it takes 11 hours to fill the pool)

Now, we can calculate the fraction of the pool that remains unfilled after 1 hour by subtracting the combined rate of both pipes from 1.

Let's denote the fraction of the pool that remains unfilled after 1 hour as F.

F = 1 - (R1 + R2)

Let's calculate the value of F:

F = 1 - (1/9 + 1/11)

F = 1 - (11/99 + 9/99)

F = 1 - (20/99)

F = 79/99

Therefore, after 1 hour, approximately 79/99 or 0.798 (rounded to three decimal places) of the pool remains unfilled.

Answer

After 1 hour, approximately 79/99 or 0.798 (rounded to three decimal places) of the pool remains unfilled.