Lori has 60% of the book to read. If she has read 120 pages how many pages does she still have to read
Ok, so 120 pages plus the 60% of the book she has left to read will give the total number of pages.
That means that 120 pages is 40% of the book.
Make a proportion
120/40% = x/60%
72 = .4 x
x = 180 pages