Which expression is equivalent 3m+1-m?
2+m-1+m
1+m
3m-1
3m

200 grams.

Step-by-step explanation:

-We are given the total weight of the bag as 500grams

-Also given is, 20000cg of red marbles and 1000 dg of yellow balls and blue marbles.

#First we convert all units into grams:

#we then subtract the sum of the given weights from the total weights to get weight of the blue marbles:

Hence, the weight of the blue marbles is 200 grams.