Answer: 286
Explanation:
Let the number of non fiction books be 'x'
Then the number of fiction books = 11x
Total books in Mark's bookcase= 312
According to the given situation the equation will be
![x+11x=312\\\Rightarrow12x=312..............[\text{combine like terms}]\\\Rightarrow\ x=26.......[\text{divide 12 on both sides}]](https://img.qammunity.org/2016/formulas/mathematics/middle-school/6cvy68x695hozmb1f2hm181y3hfi4x2dvh.png)
Hence, the number of non fiction books=26
and the number of Fiction books =
