Answer:
6
Step-by-step explanation:
We can think of the 10 black bags as 2 sets of 5-black bags (10 divided into groups of 5; 10 / 5 ; is 2 groups/sets). So, we would also have two sets of 3 (3 x 2 = 6), or 6 bags.
5 : 3 = 10 : 6
(multiply both numbers by 2)
