Решение:
- \( 40 \cdot (18 : 9) = 40 \cdot 2 = 80 \)
- \( 5 \cdot 8 : 20 = 40 : 20 = 2 \)
- \( 30 \cdot (24 : 8) = 30 \cdot 3 = 90 \)
- \( 10 \cdot 8 : 40 = 80 : 40 = 2 \)
- \( 20 \cdot (24 : 6) = 20 \cdot 4 = 80 \)
- \( 90 : (5 \cdot 6) = 90 : 30 = 3 \)
Ответ: 80; 2; 90; 2; 80; 3.