Question

Одна бригада рабочих может заасфальтировать 18 км дороги за 30 дней, а другая в 2 раза дольше. За сколько дней смогут заасфальтировать эту дорогу обе бригады, работая вместе? Решение в 5 действий

Answer 1

1) производительность первой бригады 18/30=0,6 км в день

2) вторая бригада выполнит работу за 2*30=60 дней

3) производительность второй бригады 18/60=0,3 км в день

4) общая производительность 0,6+0,3=0,9

5) совместно работая обе бригады выполнят работу за 18/0.9=20 дней

Answer 2

Problem Analysis

We are given two teams of workers. The first team can pave 18 km of road in 30 days, while the second team takes twice as long. We need to determine how many days it will take for both teams to pave the road together.

Solution

To solve this problem, we can follow these steps:

1. Calculate the rate at which each team paves the road. 2. Determine the combined rate of both teams. 3. Use the combined rate to calculate the number of days required to pave the road.

Let's calculate the solution step by step.

Step 1: Calculate the rate at which each team paves the road

The first team can pave 18 km of road in 30 days. Therefore, their rate of paving is 18 km / 30 days.

The second team takes twice as long as the first team. Therefore, their rate of paving is 18 km / (30 days * 2).

Step 2: Determine the combined rate of both teams

To determine the combined rate of both teams, we need to add their individual rates. Let's calculate it:

Combined rate = Rate of Team 1 + Rate of Team 2

Step 3: Use the combined rate to calculate the number of days required to pave the road

To calculate the number of days required to pave the road, we can use the formula:

Number of days = Total distance / Combined rate

Now, let's substitute the values and calculate the solution.

Solution Calculation

1. Calculate the rate at which each team paves the road: - Rate of Team 1 = 18 km / 30 days = 0.6 km/day - Rate of Team 2 = 18 km / (30 days * 2) = 0.3 km/day 2. Determine the combined rate of both teams: - Combined rate = Rate of Team 1 + Rate of Team 2 = 0.6 km/day + 0.3 km/day = 0.9 km/day

3. Use the combined rate to calculate the number of days required to pave the road: - Number of days = Total distance / Combined rate = 18 km / 0.9 km/day = 20 days

Answer

Both teams, working together, will be able to pave the road in 20 days.

Please let me know if I can help you with anything else.