Answer:
Mary has 12 marbles.
Step-by-step explanation:
In order for 5/6 to equal 10, we would have to make groups of twos to represent the striped marbles. In this case, we would have 5 twos, not only to make the ten but also to make the 5/6. Then, to finally get our remaining 1/6, we would add one more group of two, making 12.
