Final answer:
Ruby gives her sister 6 animals.
Step-by-step explanation:
To find out how many animals Ruby gives her sister, we need to follow the instructions step by step. Ruby starts with 16 stuffed animals. She gives 1/4 of her collection to her brother, which is equal to 16 * 1/4 = 4. Now Ruby has 16 - 4 = 12 stuffed animals left. Then she gives half of the remaining animals to her sister, which is equal to 12 * 1/2 = 6. So Ruby gives her sister 6 animals.