9. 1)5 целых 8/10 - 3ц 5/10 = 2ц 3/10
2) 23/10 : 1ц 1/2 = 23/10 * 2/3 = 46/30
3) 46/30 * 5/3 = 46/18
4) 46/18 + 3ц 4/9 = 46/18 + 31/9 = 46/18 + 62/18 = 108/18 = 6
Ответ: 6
11. x - красн., х+30% - син.
1)х + х + 30% = 100%
2х = 70%
х = 35%
х + 30% = 65%
2)920 г - 100%
у г - 65%
3) у=(920*65)/100=46*13=598
Ответ: 598 грам.