Respuesta :

It will take Kelly 25 hours to read her 300 paged book

First you set up a proportion (30/6 = 300/x) 
Then you cross multiply (6*300) (30*x) 
1800 = 30x

Then you'll divide 30 to each side (1800/30) 
x=60
It'll take her 60 hours to read the entire book