(4 5/6 - 2,5) * 12 - 27 * 5/9 = 13,
1) 4 5/6 - 2,5 = 29/6 - 25/10 = 145/30 - 75/30 = 70/30 = 7/3 = 2 1/3,
2) 2 1/3 * 12 = 7/3 * 12 = 7 * 4 = 28,
3) 27 * 5/9 = 3 * 5 = 15,
4) 28 - 15 = 13
14×5-14×3/21×9+21×3=14(5-3)/21(9+3)=4/36=1/9
108)
1724:10=172 (ост4) проверка: 172·10+4=1724
2540:100=25 (ост40) 25·100+40=2540
65032:1000=65 (ост32) 65·1000+32=65032