Actually, it is pages left=total pages-pages read pages read=(number of pages per hour) times (number of hours) numbe rof pages per hour=40 x=number of hours 254=total pages so y=254-40x, not 4x
what is the question if it is how many hours to read the book then 0=pages left 0=254-40x add 40x to both sides 40x=254 divide by 40 x=6.35 6.35 days or aprox 7 days
equation is y=254-40x where y=pages left and x=number of hours read