If 357 means “books are costly”, 467 means “read good books”, 5678 means “good books are available”.

What is the code for costly?

**ANSWER: 3** = costly.

357 means “books are costly” (1)

467 means “read good books” (2)

5678 means “good books are available”. (3)

- common of (1) and (2) number 7 and “books” so 7 = books.
- common of (2) and (3) number 67 = “good books”. If 7=books then 6 = good
- from (2) ==> 6 = good, 7 = books then 4 = read.
- common of (1) and (3) number 5 and 7 and “books are”==> 5 = are
- from (1) == > 5 = are, 7 = books then 3 = costly.