The equation given below shows this relationship, where x represents the number of marbles Beth has, and y represents the number of marbles Amy has.
x=4y
If Beth has 48 marbles, how many marbles does Amy have?
If x = 48, then we can substitute this value in the equation:
48 = 4y
To solve for y, we can divide both sides by 4:
48/4 = y
12 = y
Therefore, Amy has 12 marbles.