This site has your answer.
http://74.125.47.132/search?q=cache:Ac9h9imW5s0J:www.mpcfaculty.net/alfred_hochstaedter/Geology/lab/04%2520topomaps.pdf+fractional+scale+of+a+quad&cd=2&hl=en&ct=clnk&gl=us&ie=UTF-8
What is the fractional scale of a quad?
4 answers
So then the fractional scale of this quad on the map of Menan Butte, Idaho would be 1:24,000. Is this correct? Thanks.
Yes. That's correct.
How far—to the nearest tenth of a kilometer—is the well in section 11 from the southwest corner of section 10?