Answer:
10 years old
Explanation:
Let's say the age of the younger sister is x. Then the age of the older sister must be x + 2 because the ages are consecutive even numbers.
"Twice the age of the youngest exceeds the oldest by 8" means that we multiply x by 2 and set that equal to (x + 2) + 8:
2x = (x + 2) + 8
2x = x + 10
x = 10
So, the youngest sister is 10 years old.