Answer:
See image
Step-by-step explanation:
An equation is really like a scale with two equal things on both sides. You could use the idea of a scale and lift off the same amount from both sides to keep it balanced. But I will show you the algebra version. When we subtract the same thing from both sides that's how we work back to our answer while keeping the scale balanced.
Let m = weight of a marble
p = weight of a penny = 1 gram
q = weight of a quarter= 3 grams
The problem says how many of each marble, penny, quarter, then set them equal to each other. See image
