There are dozens of books which contain papers and solutions. The exam used to be called the senate-house examination a while ago, hence the titles. 'Tripos' is derived from the way the exam was taken, where you had to sit on a 3-legged wooden stool and "wrangle" - argue through problems orally - with the examiners. ('Riders' are just the first few parts of a problem, which are usually simple book-work questions in order to allow the weaker candidates to gain some points on the exam.) To name a few:
- Cambridge senate-house problems and riders, with solutions, 1875 - Greenhill
- Cambridge senate-house problems and riders, with solutions, 1878 - Glaisher
- Mathematical problems for Cambridge Mathematical Tripos - Wolstenholme (I remember seeing a solutions manual to this somewhere, but it might be called something weird like "Key to..." instead of "Solutions to...".)
- Cambridge senate-house problems and riders, 1848-1851 - Ferrers
- Cambridge senate-house problems and riders, 1843-1851 - Jameson
- Cambridge senate-house problems and riders, 1854 - Walton
- Cambridge senate-house problems and riders, 1857 - Walton
You can easily discover more by searching "cambridge senate house" on archive.org. Other useful terms include: "cambridge problems and riders", "cambridge senate house solutions", "problems cambridge examinations", "cambridge examples", etc.