Answer:
Sydney is 9 years old.
Step-by-step explanation:
Since Devaughn is two times Sydney's age, and their ages sum up to 27, you have to divide 27 by 3.
After dividing 27 by 3, you get 9.
9 + 9 = 18 (Devaughn's age)
So 18 + 9 = 27, which is the sum of their ages.