The time it takes to complete a task is inversely proportional to the number of people working on it, assuming all people work at the same rate.

Given:

• 3 people take 8 hours to fill in the pond.

To calculate how long it would take for 5 people working at the same rate, we can use the formula:

$\text{time with } n_2 \text{ people} = \frac{n_1 \times t_1}{n_2}$

Where:

• $n_1 = 3$ (number of people initially),
• $t_1 = 8$ hours (time for 3 people),
• $n_2 = 5$ (new number of people).

Substituting these values:

$\text{time with 5 people} = \frac{3 \times 8}{5} = \frac{24}{5} = 4.8 \text{ hours}.$

So, it would take 5 people approximately 4.8 hours to fill in the pond.

Would you like more details or have any questions?

Here are some related questions:

1. What if 4 people worked together at the same rate?
2. How long would it take if 6 people worked on it?
3. What if 2 people worked together, how long would it take them?
4. How many people would be needed to complete the task in 3 hours?
5. How does the rate of work change if one person worked alone?

Tip: When the number of workers increases, the time to complete the task decreases proportionally.