Introduction

Here's a little puzzle. Which is better to place books horizontally or vertically? Which one takes less space, is more efficient, and is finally better? 

Here's the problem. 

Shelf dimension (space inside the shelf) 

Width = 40 cm 

Height = 20 cm 

Book dimensions 

Height of book = 10 cm 

Width (front cover) = 8 cm 

Thickness of each book = 1 cm 

Try to solve it if you like, then look at the results. 

Here is the math done. 

Standing books normally like it's usually done. 

• Height needed by the book: 10 cm. You can fit 2 rows (20 ÷ 10 = 2).
• Width used by thickness: needed 1 cm by book, 40 books per row

Total:

40 × 2 = 80 books

So in total in a space of 40 by 20 you can fit 80 books. 

Books stacked flat (lying down)

• Now books are placed like piles.
• The width of the book is 8 cm, so: 8 cm → 40 ÷ 8 = 5 stacks
• Height used: 1 cm per book; 20 ÷ 1 = 20 books per stack, and there are 5 stacks. 

Total:

5 × 20 = 100 books

So in a total space of 40 by 20 you can fit 100 BOOKS. 

Results 

So as you see, stacked lying down can fit more books and is more efficient—20 more. But is it a good idea? 

Is it a good idea? 

• Stacked like this, it could be harsher for books to be reached. 
• As with case 1, it could be pulled and the book seen. 
• Books are vulnerable to tears when pulled and are destroyed more easily. 
• Could be more efficient for space. 

Conclusion 

We transformed a simple problem into a fun game and a study of what is better when stacking books. 

Have you got it right? And what do you think about the difference between the two?