8x= 1000-440

8x=560

x=70

2. The number of Kobayashi stamps+the number of Xiaojun stamps = the total number of stamps.

Solution: If there are X Kobayashi, then there are 3x small armies.

x+3x=240

4x=240

x=60

3x= 180

3. Number of banyan trees+number of pine trees = total number of trees.

Solution: If there are x banyan trees, there are 2x pine trees.

x+2x= 120

3x= 120

x=40

2x=80

4. Number of roosters+number of hens = total.

Solution: If there are X cocks, there are (2x+30) hens.

x+(2x+30)=480

3x+30=480

3x=450

x= 150

2x+30=330

5. Stored grain in warehouse A = stored grain in warehouse B..

Solution: If warehouse B originally stored X tons of grain, warehouse A originally stored 3 tons of grain.

3x-90=x- 10

2x=80

x=40

3x= 120

6. Total sugar = total sugar

Solution: Let's have X children.

6x+80=8x-20

100=2x

x=50

50× 6+80 = 380 (piece)