(3 9/16-у)+4 9/16=5 7/16
3 9/16-у=5 7/16-4 9/16 5 7/16-4 9/16=4 23/16-4 9/16=14/16
3 9/16-у=14/16
у=3 9/16-14/16 3 9/16-14/16=2 25/16-14/16=2 11/16
у=2 11/16
проверка (3 9/16-2 11/16)+4 9/16=5 7/16
(2 25/16-2 11/16)+4 9/16=5 7/16
14/16+4 9/16=5 7/16
4 23/16=5 7/16
5 7/16=5 7/16