Question

In 2010, a library contained a total of 11500 books in two categories -fiction and nonfiction. In 2015, the library contained a total of 12760 books in these two categories. During this period, there was 10% increase in the fiction category while there was 12% increase in the non-fiction category. How many fiction books were in the library in 2015?

• A. 6000
• B. 6160
• C. 5500
• D. 6600

Answer 1

Answer: (D)

6600

Answer 2

Let the number of fiction and non-fiction books in 2010 be represented by x and y, respectively.

From the first condition:
$x+y=11500 ........... (1)$
From the second condition:
$1.1x+1.2y=11500............... (2)$
Solving both equations, we find that $x = 6000.$

In 2015, the number of fiction books is given by $1.1x=6600.$