Question

305. Монеты разделили на несколько кучек. В одну кучку положили монеты по 5 к, во вторую по 10 к, в третью - ПО 20 к. По количеству монет кучки соотносятся между собой как 7 : 4:3. Если пятикопеечные монеты в сумме составляют 70 к, какую сумму составляют все монеты?

Answer 1

70:80:120 если я всё правильно понял то так

Answer 2

Problem Analysis

We are given that coins are divided into several piles. One pile contains coins worth 5 kopecks each, another pile contains coins worth 10 kopecks each, and the third pile contains coins worth 20 kopecks each. The number of coins in the piles is in a ratio of 7:4:3. We are also given that the total value of the 5-kopeck coins is 70 kopecks. We need to find the total value of all the coins.

Solution

Let's assume that the number of coins in the first pile (worth 5 kopecks each) is 7x, the number of coins in the second pile (worth 10 kopecks each) is 4x, and the number of coins in the third pile (worth 20 kopecks each) is 3x.

We are given that the total value of the 5-kopeck coins is 70 kopecks. Therefore, we can write the equation:

5 * 7x = 70

Simplifying the equation, we find:

35x = 70

Dividing both sides of the equation by 35, we get:

x = 2

Now, we can find the number of coins in each pile:

- Number of coins in the first pile (worth 5 kopecks each) = 7x = 7 * 2 = 14 - Number of coins in the second pile (worth 10 kopecks each) = 4x = 4 * 2 = 8 - Number of coins in the third pile (worth 20 kopecks each) = 3x = 3 * 2 = 6

To find the total value of all the coins, we need to calculate the sum of the values of the coins in each pile:

- Value of coins in the first pile = 5 kopecks * 14 = 70 kopecks - Value of coins in the second pile = 10 kopecks * 8 = 80 kopecks - Value of coins in the third pile = 20 kopecks * 6 = 120 kopecks

Adding up the values of the coins in each pile, we get:

70 kopecks + 80 kopecks + 120 kopecks = 270 kopecks

Therefore, the total value of all the coins is 270 kopecks.

Answer

The total value of all the coins is 270 kopecks.