This means there were 500 books in a school library. 70% of these were fiction books. some new books were added to the library
the afternoon. as a result, the number of fiction books increased by
20% and the number or non-fiction books increased to 80% of the books in the
library. how many fiction books were added to the library this afternoon?

70 fiction books were added to the library .

Step-by-step explanation:

there were 500 books.

70% of these were fiction books.

so,

fiction books  were =(500 x 70/100)

                                  =350

now,

these were 350 fiction books

Some new books were added to the library . As a result, the number of fiction books increased by  20%.

so,

the number of fiction books were added =350 x 20%

                                                                      =350 x 20/100

                                                                        =70  

what

236 cm 16 time 12 = 192

6 times 7 = 42

192+42