There would be 8 red marbles and 47 purple marbles.
Step-by-step explanation:
In order to find this, we can first set the amount of red marbles as x. Once we do this, it is possible to model the number of purple marbles as 5x + 7. Knowing this, we can add the two together and set equal to 55.
x + 5x + 7 = 55
6x + 7 = 55
6x = 48
x = 8
With 8 red marbles, we know the rest must be purple (47)
