Jose has a comic book collection that he keeps among 5 shelves with an equal number on each shelf. His father adds 20 comic books to the bottom shelf, so the shelf now has 125 books. How many total books are in his collection? Use algebra to solve the equation.(1 point)

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1 answer

Let \( x \) be the number of comic books on each shelf before the father adds 20 comic books to the bottom shelf. Since there are 5 shelves, the total number of comic books in his original collection can be expressed as:

\[ 5x \]

After his father adds 20 comic books to the bottom shelf, the number of books on that shelf becomes:

\[ x + 20 \]

According to the problem, the bottom shelf now has 125 comic books. Therefore, we can set up the equation:

\[ x + 20 = 125 \]

To solve for \( x \), subtract 20 from both sides:

\[ x = 125 - 20 \] \[ x = 105 \]

Now, we can find the total number of comic books in Jose's collection by substituting \( x \) back into the expression for the total number of books:

\[ 5x = 5(105) = 525 \]

Thus, the total number of comic books in Jose's collection is:

\[ \boxed{525} \]