A 60-page book has n lines per page. If the number of lines were reduced by 3 in each page, the number of pages would have to be increased by 10 to give the same writing space. What is the value of n?
- A. 18
- B. 21 ✓
- C. 24
- D. 30
Correct Answer: B. 21
Explanation
Total lines = 60n. After changes, pages = 60+10 = 70 and lines/page = n-3. Equating the two: 60n = 70(n-3) \Rightarrow 60n = 70n - 210 \Rightarrow 10n = 210 \Rightarrow n = 21.
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