Tyler reads 2/15 of a book on monday, 1/3 of it on tuesday, 2/9 of it on wednesday, and 3/4 of the remainder on thursday, if he still has 14 pages left to read on friday, how many pages are there in the book

The first thing you should do is convert those fractions you have to percentages to then be able to get the number of pages of the book.
 Monday: (2/15) * 100 = 13.33333333%
 Tuesday: (1/3) * 100 = 33.33333333%
 Wednesday: (2/9) * 100 = 22.22222222%
 3/4 of the remainder on thursday:
 thursday: (100- (13.33333333 + 33.33333333 + 22.22222222) * (3/4) = 23.33333333%
 he still has 14 pages left to read on friday
 Friday:
 [100- (13.33333333 + 33.33333333 + 22.22222222)] - 23.33333333 = 7.777777778%
 Which means that 14 pages represent 7.777777778% of the book.
 Therefore the number of pages of the book is given by:
 (100 / 7.777777778) * 14 = 180.
 Answer:
 The book has 180 pages.