Using a system of equations, it is found that 1530 more novels have been bought in total.
For the system, we have that:
The ratio of the number of novels to that of dictionaries is 2:3, hence:
[tex]\frac{x}{y} = \frac{2}{3}[/tex]
[tex]3x = 2y[/tex]
[tex]y = \frac{3x}{2}[/tex]
Total number of novels is 624, hence:
[tex]x = 624[/tex]
[tex]y = \frac{3}{2} \times 624 = 936[/tex]
Buys z more novels, and the ratio becomes [tex]\frac{7}{3}[/tex], hence:
[tex]\frac{624 + z}{923} = \frac{7}{3}[/tex]
[tex]1872 + 3z = 6461[/tex]
[tex]z = \frac{6461 - 1872}{3}[/tex]
[tex]z = 1530[/tex]
1530 more novels have been bought in total.
A similar problem is given at https://brainly.com/question/17096268