Sure! Here's a math problem similar to the one you've described:

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Problem: A person is reading a book. On the first day, he read 50 pages. On the second day, he read 30% of the remaining pages. After these two days, there are 120 pages left to read.

Question:
How many pages are there in the book, and how many pages has the person read so far?

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Solution Approach:

1. Let the total number of pages in the book be $x$.
2. After the first day, 50 pages have been read, so the remaining pages are $x - 50$.
3. On the second day, he reads 30% of the remaining pages, so he reads $0.30 \times (x - 50)$ pages.
4. After the second day, the remaining pages are 120, so we can set up the equation:

$\text{Remaining pages} = \text{Total pages} - \text{Pages read on day 1} - \text{Pages read on day 2}$

$120 = x - 50 - 0.30 \times (x - 50)$

Now, you can solve for $x$ to find the total number of pages and the number of pages read.

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Would you like me to work through the solution step by step? If you have any questions or need further clarification, feel free to ask! Here's a list of related questions:

1. How would the solution change if the person read 40% of the remaining pages instead of 30% on day 2?
2. How do you calculate the remaining pages after day 2?
3. What is the difference between this problem and a percentage increase problem?
4. Can this problem be modeled as a system of equations?
5. How would you set this up if he had read 60 pages on day one?

Tip: Always translate percentages into decimals when solving problems involving fractions of a total.