it would probably be 7, since 1 hour and 30 minutes would be 90 minutes, and she read 10 pages in that long, it would most likely be one page every 10 minutes, but since she read 10 in 90 minutes and not 9, I believe we would add 1 extra page to the amount she read in one hour, and since one hour is 60 minutes, it would probably be 6 + 1, which is 7.
