Question

Купили 5 больших и 6 маленьких пачек масла, заплатив за все большие пачки на 7 рублей больше, чем за все маленькие. Найдите стоимость покупки, если одна маленькая пачка на 5,9 рублей дешевле большой. Заранее спасибо

Answer 1

Х - стоимость маленькой пачки, х+5,9 - стоимость большой пачки
Составим и решим уравнение:
5(х+5,9)-6х=7,
5х+29,5-6х=7
-х=-22,5,
х=22,5 рублей - стоит маленькая пачка
22,5+5,9=28,4 рублей стоит большая пачка
5х28,4+22,5х6=142+135=277рублей-вся покупка

Answer 2

Problem Analysis

We are given that 5 large packs of oil cost 7 rubles more than 6 small packs of oil. We are also given that the price of one small pack is 5.9 rubles less than the price of one large pack. We need to find the total cost of the purchase.

Solution

Let's assume the cost of one small pack of oil is x rubles. Then the cost of one large pack of oil would be x + 5.9 rubles.

The total cost of 5 large packs of oil would be 5 * (x + 5.9) rubles.

The total cost of 6 small packs of oil would be 6 * x rubles.

We are given that the cost of 5 large packs is 7 rubles more than the cost of 6 small packs. So we can set up the equation:

5 * (x + 5.9) = 6 * x + 7

Now we can solve this equation to find the value of x and then calculate the total cost of the purchase.

Calculation

Let's solve the equation:

5 * (x + 5.9) = 6 * x + 7

Expanding the equation:

5x + 29.5 = 6x + 7

Rearranging the terms:

6x - 5x = 29.5 - 7

Simplifying:

x = 22.5

Now we can calculate the total cost of the purchase:

The cost of one small pack is 22.5 rubles, so the cost of one large pack would be 22.5 + 5.9 = 28.4 rubles.

The total cost of 5 large packs would be 5 * 28.4 = 142 rubles.

The total cost of 6 small packs would be 6 * 22.5 = 135 rubles.

Therefore, the total cost of the purchase is 142 + 135 = 277 rubles.

Answer

The total cost of the purchase is 277 rubles.