Posted by srihita on .
sally read 21 pages of a book on Satuday. She read 5/9 of the remainder on Sunday. If she still had 1/3 of the book left to read, how many pages were there in the book?

maths 
Reiny,
number of pages  x
at end of Saturday, number of pages left = x21
she read 5/9 of those, leaving 4/9(x21) pages
but this is supposed to be 1/3 of the pages
4/9(x21) = (1/3)x
times 9
4(x21) = 3x
4x  84 = 3x
x = 84
There were 84 pages in the book
check:
she read 21 pages on Saturday leaving 63
on Sunday she read 5/9 of that or 35 pages
leaving her with 28 pages to read
and 1/3 of 84 = 28