## FANDOM

2,499 Pages

Seventy Books is a puzzle in Professor Layton and the Last Specter.

## Puzzle

US Version

A bookcase has seven shelves each filled with 10 books of the same size.

When you choose a book, you must also take the two books above, below, to the left, and to the right of the one you actually want. If there are fewer than two books in any of these directions, you cannot choose that book.

Choosing as many books as possible, how many books will you end up taking?

UK Version

A bookcase has seven shelves each filled with ten books of the same size.

When you choose a book, you must also take the two books directly above, below, to the left and to the right of the one you actually want. If there are fewer than two books in any of these directions, you cannot choose that book.

Choosing as many books as possible, how many books will you end up taking?

## Hints

Click a Tab to reveal the Hint.

US Version

Taking two books from above, below to the left, and to the right of a book totals nine books in a cross shape, doesn't it?

See how many of these will fit into the bookcase.

UK Version

Taking two books from above, below, to the left and right of a book totals nine books in a cross shape, doesn't it?

See how many of these will fit into the bookcase.

US Version

If you try simple math, nine books multiplied by seven should make 63 books...but it's not that easy.

The key to the puzzle is in the cross shape. Use the Memo function and think carefully.

UK Version

If you try simple maths, nine books times seven should make 63 books, but it's not that easy.

The key to the puzzle is in the cross shape. Use the Memo Function and think carefully.

US Version

You must take two books in each direction as well as the book you wish to take. This limits the books that may be removed. The number of books you are allowed to take is surprisingly low.

UK Version

You must take two books in each direction, as well as the book you wish to take. This limits the books that may be removed. The number of books you are allowed to take is surprisingly low.

US Version

Don't overthink things. You can only take as many books as is physically possible.

Given that each set of nine books spans almost half of the total area of the bookcase, it should be clear how many sets you can take.

UK Version

Don't overthink things. Given that each set of nine books spans almost half of the total area of the bookcase, it should be clear how many sets you can take.

## Solution

### Incorrect

Too bad!

US Version

You have to count all the books you can take.

UK Version

You have to count all the books you must take.

### Correct

Inc-read-ible!

US Version

Eighteen books is correct.

Even though it looks like you should be able to take more, you can't because of that troublesome rule.

UK Version

18 books is correct.

Even though it looks like you should be able to take more, you can't because of that troublesome rule.

A big thanks to http://professorlayton4walkthrough.blogspot.com

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