Question

Перед началом футбольного матча продавец продал 1/2 пирожков, а в перерыве - еще 15 штук. После этого у него осталось 2/7 того количества пирожков, которые он принес для продажи. Сколько пирожков было у него вначале? (без х) помогите плиз

Answer 1

Принимаем все пирожки за одну целую часть,тогда 
1-1/2-2/7=3/14 всех пирожков продал в перерыве
15:3/14=70 пирожков принёс для продажи
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Answer 2

Problem Analysis

To solve this problem, we need to determine the initial number of pastries the seller had before selling half of them and then selling 15 more during the break. We are also given that after these sales, the seller had 2/7 of the original quantity left.

Solution

Let's assume the initial number of pastries the seller had is x.

1. The seller sold half of the pastries before the match, which is 1/2 * x. 2. During the break, the seller sold 15 more pastries, so the total number of pastries sold is 1/2 * x + 15. 3. After these sales, the seller had 2/7 of the original quantity left, which is 2/7 * x.

To find the initial number of pastries, we can set up the following equation:

1/2 * x + 15 = 2/7 * x

Now, let's solve this equation to find the value of x.

Calculation

To solve the equation 1/2 * x + 15 = 2/7 * x, we can multiply both sides of the equation by the least common multiple (LCM) of the denominators, which is 14.

14 * (1/2 * x + 15) = 14 * (2/7 * x)

Simplifying the equation:

7x + 210 = 4x

Subtracting 4x from both sides:

7x - 4x + 210 = 0

Simplifying further:

3x + 210 = 0

Subtracting 210 from both sides:

3x = -210

Dividing both sides by 3:

x = -70

Answer

The initial number of pastries the seller had was -70. However, it is not possible to have a negative number of pastries, so there might be an error in the given information or the calculations. Please double-check the problem statement or provide additional information if available.

If you have any further questions, feel free to ask!