Question

За учебный год Петя израсходовал 40% купленных в начале года тетрадей, и у него осталось 30 тетрадей. Сколько тетрадей было купленно для Пети в начале года?

Answer 1

1) 100 % -40 % = 60 % = 30 тетрадей

2) 30 х 100 % : 60 % = 50 тетрадей было куплено

Answer 2

Calculation of the Number of Notebooks Bought for Petya at the Beginning of the Year

To calculate the number of notebooks bought for Petya at the beginning of the year, we can use the information provided. It is stated that Petya used 40% of the notebooks bought at the beginning of the year and had 30 notebooks left.

Let's assume the number of notebooks bought at the beginning of the year is represented by the variable x.

According to the given information, Petya used 40% of the notebooks, which means he used 60% of the notebooks.

The equation to represent this is:

0.6x = 30

To solve for x, we can divide both sides of the equation by 0.6:

x = 30 / 0.6

Now, let's calculate the value of x:

x = 50

Therefore, Petya bought 50 notebooks at the beginning of the year.