Let's define the number of comic books on each shelf before his father adds any books. Let \( x \) be the number of comic books on each of the 5 shelves.
Initially, since there are 5 shelves with an equal number of books on each, the total number of books in the collection can be represented as: \[ 5x \]
Then, Josie's father adds 20 comic books to the bottom shelf. After this addition, the bottom shelf has: \[ x + 20 \]
According to the problem, after the addition, the bottom shelf has 125 comic books. Therefore, we can write the equation: \[ x + 20 = 125 \]
To solve for \( x \), we subtract 20 from both sides: \[ x = 125 - 20 \] \[ x = 105 \]
Now that we know there are 105 comic books on each shelf, we can find the total number of books in Josie's collection: \[ \text{Total books} = 5x = 5 \times 105 \] \[ \text{Total books} = 525 \]
Thus, the total number of books in Josie's collection is \( \boxed{525} \).
3 answers