Ivan started the week on page 35 of
his book and read 20 pages each
night. What page will Ivan be on if he
reads for 8 nights? 12 nights?
pls help

So in this question, 15 pages * 6 days = 90 pages. Which is 5/8 of the book (since we only have 3/8 left). So we have something like:

(5/8)*x = 90

where x = to the number of pages in the book.

Then (90)/(5/8) = x, which is really like saying 90*(8/5), which is equal to 144.

All in all, there are 144 pages in the book.