A container filled with 9 honeydews has a mass of 13.23 kg. The same container when filled with 6 pears has a mass of 1.35 kg. The mass of 1 honeydew is eight times the mass of 1 pear. Find the mass of the container when it is empty. Express the answer in g.
1 kg = 1000 g

13.23 kg = 13230 g
1.35 kg = 1350 g

1 pear = 1 u
6 pears = 6 x 1 u = 6 u

1 container + 6 pears = 1350
1 container + 6 u = 1350 --- (1)

1 honeydew = 8 u
9 honeydews = 9 x 8 u = 72 u

1 container + 9 honeydews = 13230
1 container + 72 u = 13230 --- (2)

(2) - (1)
72 u - 6 u = 13230 - 1350
66 u = 11880

1 u = 11880 ÷ 66 = 180

6 u = 6 x 180 = 1080

From (1):
1 container + 6 u = 1350
1 container + 1080 = 1350
 
1 container = 1350 - 1080 = 270

Mass of 1 container = 270 g

Answer(s): 270 g