Set up a proportion pages/pages= minutes/ minutes 7/175=5/x Note: x is the unkown variable or how long it will take him to read a 175 page book. --Now do the math-- or cross multiply-- 7(x)=175(5) reduce it down 7(x)=875 divide both sides by 7 in order to get variable x alone x=125 So it will take Jose 125 minutes to read the entire 175 page book.