The total weight of a flying saucer and a toy car is 2.7 kg. The total weight of a flying saucer and a toy house is 4.1 kg. If the total weight of a toy house and a toy car is 5.23 kg, find the total weight of the flying saucer, the toy car and the toy house.
Let 1 flying saucer be 1 F.
Let 1 toy car be 1 T.
Let 1 toy house be 1 H.

1 F + 1 T = 2.7 --- (1)
1 F + 1 H = 4.1 --- (2)
1 H + 1 T = 5.23 --- (3)

(1) + (2) + (3)
1 F + 1 T + 1 F + 1 H + 1 H + 1 T = 2.7 + 4.1 + 5.23
2 F + 2 T + 2 H = 12.03
2(1 F + 1 T + 1 H) = 12.03 

1 F + 1 T + 1 H = 12.03 ÷ 2
1 F + 1 T + 1 H = 6.015

 Total weight of the flying saucer, the toy car and the toy house = 6.015 kg

Answer(s): 6.015 kg