Answer:
200 grams of blue marbles
Explanation:
The bag of marbles weighs 600 grams. Within the bag there are 10,000 centigrams of red marbles and 3,000 decigrams of yellow marbles. In grams these weights are 100 grams of red marbles and 300 grams of yellow marbles. These are found by dividing centigrams by 100 since 100 centigrams = 1 gram. Then divide decigrams by 10 since 10 decigrams = 1 gram.
The reaming amount of grams is the blue marbles.
600 - 100 - 300 = 200
200 grams of blue marbles