Question

Кенан сперва потратил 1/3 части от денег, а потом потратил 2/5 части от оставшихся денег. Сколько вначале у него было денег, если у него осталось 20 рублей

Answer 1

Было х, стало 2х/3, затем оствлось 3*2х/3*5=20
6х/15=20
6х=300
х=50, Было 50 рублей

Answer 2

Problem Analysis

We are given that Kenan first spent 1/3 of his money and then spent 2/5 of the remaining money. We need to determine the initial amount of money Kenan had if he has 20 rubles left.

Solution

Let's assume the initial amount of money Kenan had is x rubles.

According to the problem, Kenan first spent 1/3 of his money, which is (1/3)x rubles. After this expenditure, he has (x - (1/3)x) = (2/3)x rubles left.

Next, Kenan spent 2/5 of the remaining money, which is (2/5) * (2/3)x = (4/15)x rubles. After this expenditure, he has ((2/3)x - (4/15)x) = (10/15)x = (2/3)x rubles left.

We are given that Kenan has 20 rubles left, so we can set up the equation:

(2/3)x = 20

To find the value of x, we can solve this equation:

(2/3)x = 20

Multiplying both sides of the equation by (3/2):

x = (20 * 3/2)

Simplifying:

x = 30

Therefore, the initial amount of money Kenan had was 30 rubles.

Answer

If Kenan has 20 rubles left and he first spent 1/3 of his money and then spent 2/5 of the remaining money, then the initial amount of money Kenan had was 30 rubles.