Question

Сначала цена костюма возросла на 5 %, а потом снизилась на 20 %. После этого цена костюма стала равна 8400 тенге. Какова первоначальная цена костюма?

Answer 1

Решение:
Обозначим первоначальную цену костюма за (х) руб,
тогда после подорожания костюма на 5%, он стал стоить:
х+х*5% :100%=х+0,05х=1,05х
после снижения цены на 20%, костюм стал стоить:
1,05х -1,05х*20% :100%=1,05х - 0,21х=0,84х
А так как цена костюма после снижения цены 20% стала, равной 8400тг,
составим уравнение:
0,84х=8400
х=8400:0,84
х=10000

Ответ: Первоначальная цена костюма 10000гг

Answer 2

Calculating the Initial Price of the Suit

To calculate the initial price of the suit, we can follow these steps:

1. Calculate the Price Increase and Decrease: - The price of the suit initially increased by 5% and then decreased by 20%.

2. Use the Final Price to Find the Initial Price: - After the increase and decrease, the final price of the suit is 8400 tenge.

3. Calculate the Initial Price: - We can use the final price and the percentage changes to calculate the initial price of the suit.

Calculation

Let's denote the initial price of the suit as x.

1. The price of the suit increased by 5%, so the price became 1.05x. 2. Then, the price decreased by 20%, so the final price became 0.8 * (1.05x), which is equal to 8400 tenge.

Now, we can solve for x:

0.8 * (1.05x) = 8400

1.05x = 8400 / 0.8

x = (8400 / 0.8) / 1.05

Calculation Result

By solving the equation, the initial price of the suit is 8000 tenge.