Question

7,210 books in a library are organized into 3 rooms. there are 1,960 more books in the first room than in the second room. the number of books in the second room is three times the number of books in the third room. how many books are in the third room?​

Answer 1

Answer:

750 books

Step-by-step explanation:

Let there be "x" number of books in the 3rd room

Now,

2nd room has 3 times as 3rd room, so we can write:

Second Room = 3x

Also, there are 1960 MORE books in 1st room than 2nd room, so we can write:

First Room = 3x + 1960

In total there are 7210 books in all three rooms, thus we can write:

First Room + Second Room + Third Room = 7210

Now, replacing the first 2 equations in this, we get:

3x + 1960 + 3x + x = 7210

Solving for x:

$3x + 1960 + 3x + x = 7210\\7x=7210-1960\\7x=5250\\x=\frac{5250}{7}\\x=750$

"x" is indeed what we are looking for. Thus,

There are 750 books in the third room