Question

Требуется окрасить 200 квадратных метров поверхности стены. 55% работы уже выполнено. Какую площадь осталось покрасить?Решите задачу двумя способами.

Answer 1

Problem Statement

You need to calculate the remaining area to be painted on a wall with a total surface area of 200 square meters. 55% of the work has already been completed. We will solve this problem using two different methods.

Method 1: Calculation

To find the remaining area to be painted, we need to subtract the area that has already been painted from the total surface area of the wall.

Given: - Total surface area of the wall: 200 square meters - Percentage of work already completed: 55%

Step 1: Calculate the area that has already been painted. - Multiply the total surface area by the percentage of work completed: 200 * 0.55 = 110 square meters.

Step 2: Calculate the remaining area to be painted. - Subtract the area that has already been painted from the total surface area: 200 - 110 = 90 square meters.

Therefore, there are 90 square meters of wall surface area remaining to be painted.

Method 2: Calculation using Proportions

Another way to solve this problem is by using proportions.

Given: - Total surface area of the wall: 200 square meters - Percentage of work already completed: 55%

Step 1: Set up a proportion to find the area that has already been painted. - Let x represent the area that has already been painted. - Set up the proportion: x / 200 = 55 / 100.

Step 2: Solve the proportion for x. - Cross-multiply: 100x = 55 * 200. - Simplify: 100x = 11000. - Divide both sides by 100: x = 110.

Step 3: Calculate the remaining area to be painted. - Subtract the area that has already been painted from the total surface area: 200 - 110 = 90 square meters.

Therefore, there are 90 square meters of wall surface area remaining to be painted.

Conclusion

Both methods yield the same result: there are 90 square meters of wall surface area remaining to be painted.