Question

Мальчик прочитал книгу за три дня. В первый день он прочитал 3/7 всей книги, а во второй день - 2/5 всей книги. Какую часть всей книги мальчик прочитал в третий день?

Answer 1

$\frac{3}{7} + \frac{2}{5} = \frac{5*3}{7*5} + \frac{7*2}{5*7} = \frac{15}{35} + \frac{14}{35}= \frac{29}{35}$ - прочитал за первый и второй день
1-$\frac{29}{35} = \frac{35}{35}- \frac{29}{35} = \frac{6}{35}$ - прочитал в третий день

Answer 2

Calculation of the Boy's Reading Progress

To determine the portion of the book the boy read on the third day, we need to calculate the cumulative progress he made on the first two days and subtract it from the total book length.

1. On the first day, the boy read 3/7 of the entire book. 2. On the second day, he read 2/5 of the entire book.

To find the portion of the book he read on the third day, we need to subtract the cumulative progress from the total book length:

Total book length - (Progress on the first day + Progress on the second day) = Progress on the third day

Let's calculate it step by step.

Calculation Steps

Step 1: Convert the fractions to a common denominator.

The common denominator for 7 and 5 is 35.

3/7 = 15/35

2/5 = 14/35

Step 2: Calculate the cumulative progress on the first two days.

Cumulative progress = 15/35 + 14/35 = 29/35

Step 3: Calculate the portion of the book the boy read on the third day.

Progress on the third day = 1 - 29/35 = 6/35

Therefore, the boy read 6/35 of the entire book on the third day.

Answer

The boy read 6/35 of the entire book on the third day.

Please note that the search results provided by You.com did not contain specific information about this particular question. The calculation was done based on the given fractions and the assumption that the book was read continuously over three days.