A bottle fully contains honey. The honey bottle weighed 1.5kg. Then the bottle was weighed with half of the honey, it was 900 grams. Now guess what would be the weight of the bottle?
Let the bottle weight be x
Let the honey weight be y
The weight of the bottle with honey is 1.5kg
Therefore x + y = 1500 grams -> (1)
Then the weight of the bottle with half of the honey is 900 grams
Therefore x + (y/2) = 900 grams
That is 2x + y = 1800 -> (2)
Solving the first and second equation
2x + y = 1800
x + y = 1500
x = 300
Therefore the weight of the bottle is 300 grams.