(81:9+12•3): 5+ (3•4+51): 3 =

Решение:

1. \( 81 : 9 = 9 \)
2. \( 12 \cdot 3 = 36 \)
3. \( 3 \cdot 4 = 12 \)
4. \( 9 + 36 = 45 \)
5. \( 12 + 51 = 63 \)
6. \( 45 : 5 = 9 \)
7. \( 63 : 3 = 21 \)
8. \( 9 + 21 = 30 \)

Ответ: 30