There were a total of 130 pages.
Let the total number of pages be x
Monday: 52 pages read
Tuesday:1/6 (x - 52) or x/6 - 52/6 pages read
Remaining pages left to be read: 1/2 (x)
Equation:
52 + (x/6 - 52/6) + 1/2(x) = x
LCD: (6) (2)
52 (6)(2) + 2x - 104 + 6x = x (6)(2)
624 - 104 + 2x + 6x = 12x
520 + 8x = 12x
520 = 12x - 8x
520 = 4x
520/4 = 4x/4
x = 130 pages
To check:
Monday: 52 pages
Tuesday: 1/6 (130-52) = 1/6 (78) = 13 pages
Pages left to be read: 1/2 (130) = 65 pages
Add the pages:
52 + 13 + 65 = 130
130 = 130