Question

Реши задачу разными способами В одной бочке 20 ведер воды,а в другой- на 15 меньше.Для полива взяли 5ведер воды.Сколько ведер воды осталось в бочках?

Answer 1

20-15 =5 это 2 бочка    20-5=15 осталось когда взяли    15 + 5=20 осталось                                               

Answer 2

1) х=20+(20-15)-5

х=20 л осталось в бочках

2) 20-15=5

20+5=25

25-5=20 л осталось в бочках

Answer 3

Problem Analysis

We are given two barrels of water. The first barrel contains 20 buckets of water, while the second barrel contains 15 buckets less than the first barrel. We are told that 5 buckets of water are taken for watering. We need to determine how many buckets of water are left in the barrels.

Solution 1: Direct Calculation

To solve this problem, we can directly calculate the number of buckets of water left in the barrels.

Let's denote the number of buckets in the first barrel as x. According to the problem, the second barrel contains 15 buckets less than the first barrel, so the number of buckets in the second barrel is x - 15.

We are told that 5 buckets of water are taken for watering. Therefore, the number of buckets of water left in the first barrel is x - 5, and the number of buckets of water left in the second barrel is (x - 15) - 5.

To find the value of x, we can set up an equation based on the given information:

x - 5 + (x - 15) - 5 = 0

Simplifying the equation, we get:

2x - 25 = 0

Solving for x, we find:

x = 12.5

Since the number of buckets must be a whole number, we round down to the nearest whole number. Therefore, the number of buckets in the first barrel is 12, and the number of buckets in the second barrel is 12 - 15 = -3 (which is not possible).

Therefore, there are no buckets of water left in the second barrel, and the first barrel has 12 buckets of water left.

Solution 2: Using Algebra

Another way to solve this problem is by using algebra.

Let's denote the number of buckets in the first barrel as x. According to the problem, the second barrel contains 15 buckets less than the first barrel, so the number of buckets in the second barrel is x - 15.

We are told that 5 buckets of water are taken for watering. Therefore, the number of buckets of water left in the first barrel is x - 5, and the number of buckets of water left in the second barrel is (x - 15) - 5.

We can set up an equation based on the given information:

x - 5 + (x - 15) - 5 = 0

Simplifying the equation, we get:

2x - 25 = 0

Solving for x, we find:

x = 12.5

Since the number of buckets must be a whole number, we round down to the nearest whole number. Therefore, the number of buckets in the first barrel is 12, and the number of buckets in the second barrel is 12 - 15 = -3 (which is not possible).

Therefore, there are no buckets of water left in the second barrel, and the first barrel has 12 buckets of water left.

Solution 3: Using Subtraction

We can also solve this problem by using subtraction.

The first barrel contains 20 buckets of water, and the second barrel contains 15 buckets less than the first barrel. Therefore, the second barrel contains 20 - 15 = 5 buckets of water.

5 buckets of water are taken for watering, so the number of buckets of water left in the first barrel is 20 - 5 = 15.

Therefore, there are 15 buckets of water left in the first barrel, and 5 buckets of water left in the second barrel.

Conclusion

In summary, there are different ways to solve this problem. According to the direct calculation and algebraic methods, there are no buckets of water left in the second barrel, and the first barrel has 12 buckets of water left. Using the subtraction method, there are 15 buckets of water left in the first barrel and 5 buckets of water left in the second barrel.