Algebra 3 - Greatest Common Denominator (19xx)(-) ROM Download can be obtained free for Sinclair ZX81 on EmuGames.net only. Play emulator game in English for the USA region. Algebra 3 Greatest Common Denominator is a Sinclair ZX81 ROM that you can download to your computer or play online within your browser. You can also download roms such as Indiana Jones' Greatest Adventures and Greatest Heavyweights Of The Ring that work on all devices including desktop and mobile. Be sure to rate the game if you enjoyed playing this ROM.