The school library has 2400 books on science, technology and literature. The number of literature and art books is four times that of science and technology books. How many books are there respectively? computing formula Number of science and technology books:

2400÷( 1+4),

=2400÷5,

=480 (Ben),

Number of literary books: 480×4= 1920 (book),

Or 2500-480= 1920 (Ben),

A: There are 480 books on science and technology and 1920 books on literature and art.