The left pan of a weighing balance has two weights of 500 g each, while the right pan has a bag of sugar and a weight of 100 g. If the pans are balanced, then the bag of sugar weighs ___.
The correct option is C 900 g
Total weight on the left pan
= 500 g + 500 g
= 1000 g
Total weight on the right pan
= Weight of the bag of sugar + 100 g
Since the pans are balanced, the weight on the right pan equals that on the left pan.
Therefore, the weight of the bag of sugar + 100 g = 1000 g.
Since 900 g + 100 g = 1000 g, the bag of sugar weighs 900 g.